Chapter 1 Particle KinematicsI) Choose one correct answer among following choices1. An object is moving along the x-axis with position as a function of time given byx=x(t). Point O is at x=0. The object is definitely moving toward O when2. An object starts from rest at x=0 when t=0. The object moves in the x direction with positive velocity after t=0. The instantaneous velocity and average velocity are related byA. v vB. v vC. v vdx x can be larger than, smaller than, or equal to3. An object is moving in the x direction with velocityA. Negative.B. Zero.C. Positive.D. Not determined from the information given. 4. An object is moving on the xy-plane with position as a function of time given by r = 2 2 a t i + b t j (a and b are constant). Which is correct?A. The object is moving along a straight line with constant speed.B. The object is moving along a straight line with variable speed.C. The object is moving along a curved path with constant speed.D. The object is moving along a curved path with variable speed.5. An object is thrown into the air with an initial velocity v 0 (4.9i 9.8 j)m/s.Ignore theair resistance (空气阻力 ). At the highest point the magnitude of the velocityis ( )(A) 0 (B) 4.9m/s (C) 9.8m/s (D) (4.9)2 (9.8) 2 m/s6. Two bodies are falling with negligible air resistance, side by side, above a horizontalplane. If one of the bodies is given an additional horizontal acceleration during its descent, it A. dx 0 dt B. dx 0 dt C. d(x 2) dt D. d(x 2) dtD.v x (t), and x is nonzero x dtconstant. With v x 0 when t=0, then for t>0 the quantity v x dv x v xdt isA.strikes the plane at the same time as the other body.B.strikes the plane earlier than the other body.C.has the vertical component of its velocity altered.D.has the vertical component of its acceleration altered.7. A toy racing car moves with constant speed around the circle shown below. When it is at point A its coordinates are x=0, y=3m and its velocity is 6m/s i . When it is atpoint B its velocity and acceleration are:22A.-6m/s j and 12m/s i , respectively.B. 6m/s j and -12m/s i , respectively.22C. 6m/s j and 12m/s i , respectively.D. 6m/s j and 2m/s i , respectively.8. A stone is tied to a 0.50-m string and whirled at a constant speed of 4.0m/s in a vertical circle. Its acceleration at the bottom of the circle is:2 2 2 2A. 9.8m/s , upB. 9.8m/s , downC. 8.0m/s , upD. 32m/s , up9. A boat is able to move through still water at 20m/s. It makes a round trip to a town3.0 km upstream. If the river flows at 5m/s, the time required for this round trip is:B.150 sC. 200 sD. 320 sA. 120 sII)Fill in the empty space with correct answer1. A particle goes from x=-2m, y=3m, z=1m to x=3m, y=-1m, z=4m. Its displacement is : .2.The x-component of the position vector of a particle is shown in the graph in Figureas a function of time.(a)The velocity component v x at the instant 3.0 s is .(b)When is the velocity component zero ? The time is .(c)Is the particle always moving in the same direction along the x-axis? .23.The angle turned through by a wheel is given byθ ＝at+bt , where a and b are constants. Its angular velocityω ＝, and its angular accelerationβ ＝4.When a radio wave impinges on the antenna of your car, electrons in the antennamove back and forth along the antenna with a velocitycomponent v x as shown schematically in Figure . Roughly sketchthe same graph and indicate the time instants when(a)The velocity component v x is zero;(b)The acceleration componenta x is zero;(c)The acceleration has its maximum magnitude.5. A car is traveling around a banked, circular curve of radius 150 m on a test track. At the instant when t=0s, the car is moving north, and its speed is 30.0 m/s but decreasing uniformly, so that after 5.0 s its angular speed will be 3/4 that it was when t=0s. The angular speed of the car when t=0s is , the angular speed 5.0 s lateris , the magnitude of the centripetal acceleration of the car when t=0s is , the magnitude ofthe centripetal acceleration of the car when t=5.00s is , the magnitude of the angular acceleration is , the magnitude ofthe tangential acceleration is .6. A projectile is launched at speed v 0 at an angle θ (withthe horizontal) from the bottom of a hill of c onstant slope asshown in Figure. The range of the projectile up the slope is .III) Calculate Following Problems:1. An object with mass m initially at rest is acted by a force F k 1i k 2tj , where k 1and k 2 are constants. Calculate the velocity of the object as a function of time.2. You are operating a radio-controlled model car on a vacant tennis court. Your position is the origin of coordinates, and the surface of the court lies in the xy-plane. The car, which we represent as a point, has x- and y-cooridnates that vary with time2 23 3 according to x=2.0m-(0.25m/s )t , y=(1.0m/s)t+(0.025m/s )t . a. Find the car's instantaneous velocity at t=2.0s.b. Find the instantaneous acceleration at t=4.0s.23. An object moves in the xy-plane. Its acceleration has components a x =2.50t and a y =9.00-1.40t. At t=0 it is at the origin and has velocity v 0 1.00i 7.00 j .Calculate the velocity and position vectors as functions of time.24. An automobile whose speed is increasing at a rate of 0.600 m/s travels along a circular road of radius 20.0 m. When the instantaneous speed of the automobile is 4.00 m/s, find (a) the tangential acceleration component, (b) the radial acceleration component, and (c) the magnitude and direction of the total acceleration.25. Heather in her Corvette accelerates at the rate of (3.00i -2.00 j ) m/s , while Jill in2her Jaguar accelerates at (1.00i +3.00 j ) m/s . They both start from rest at the originof an xy coordinate system. After 5.00 s, (a) what is Heather ' s speed with respect to Jill, (b) how far apart are they, and (c) what is Heather ' s acceler atoti oJnill ?re lativeChapter 2 Newton 's laws of motionI) Choose one correct answer among following choices1. In the SI, the base units (基本单位 ) for length, mass, time are ( )(A) meters, grams, seconds. (B) kilometers, kilograms, seconds.(C) centimeters, kilograms, seconds. (D) meters, kilograms, seconds.2. Which one of the following has the same d imension (量纲) as time ( )3. Which of the following quantities are independent (无关 ) of the choice of inertialx (A) (D) vx(B) (C)frame(惯性系 )?(A)v (B) P (C)F (D) W4.Suppose the net force F on an object is a nonzero constant. Which of the following could also be constant?A. Position.B. Speed.C. Velocity.D. Acceleration.5.An object moves with a constant acceleration a. Which of the following expression is also constant? ( )(A) dvdt(B)dvdt(C)d(v2)dt dt6. An object moving at constant velocity in an inertial frame must:A. have a net force on it.B. eventually stop due to gravity.C. not have any force of gravity on it.D. have zero net force on it.7. A heavy ball is suspended as shown. A quick jerk on the lower string will break that string but a slow pull on the lower string will break the upper string. The first result occurs because:A. the force is too small to move the ballB. action and reaction is operatingC. the ball has inertiaD. air friction holds the ball back8. A constant force of 8.0 N is exerted for 4.0 s on a16-kg object initially at rest. The change in speed of this object will be:A. 0.5m/sB. 2m/sC. 4m/sD. 8m/s9. A wedge rests on a frictionless horizontal table top. Anobject with mass m is tied to the frictionless incline of thewedge as shown in figure. The string is parallel to theincline. If the wedge accelerates to the left, when the objectleaves the incline, the magnitude of its acceleration isA. gsinθB. gcosθC. gtanθD. gcotθ10. A crane operator lowers a 16,000-N steel ball with a downward acceleration of 23m/s . The tension force of the cable is:A. 4900NB. 11, 000NC. 16, 000ND. 21, 000N 11. A 1-Npendulum bob is held at an angle θ from the vertical by a 2-Nhorizontal force F as shown. The tension in the string supportingthe pendulum bob (in newtons) is:A. cos θB. 2/ cos θC. 5D. 1212. A car moves horizontally with a constant acceleration of 3m/s . A ball is suspended by a string from the ceiling of the car. The ball does not swing, being at rest with respect to the car. What angle does the string make with the vertical?A. 17?B. 35?C. 52?D. 73?13. A 32-N force, parallel to the incline, is required to push a certain crate at constant velocity up a frictionless incline that is 30? above the horizontal. The mass of the crate is:A. 3.3kgB. 3.8kgC. 5.7kgD. 6.5kg II) Fill in the empty space with correct answer1. A2.5 kg system has an acceleration a (4i )m s2 . There are two forces acting on the system, and One of the forces is F1 (3i 6j)N . The other force is .2. Two masses, m1 and m2, hang over an ideal pulley and the system is free to move. The magnitude of the acceleration a of the system of two masses is Themagnitude of the tension in the cord is .3. You are swinging a mass m at speed v around on astring in circle of radius r whose plane is 1.00 m abovethe ground as shown in Figure. The string makes anangle θ with the vertical direction.(a) Apply Newton' s econd law to the horizontal andvertical direction to calculate theangle θ is .(b) If the angle θ = 47.4 a°nd the radius of the circle is1.50 m, the speed of the mass is .(c) If the mass is 1.50 kg, the magnitude of the tensionin the string is(d) The string breaks unexpectedly when the mass is movingexactly eastward. The location the mass will hit the ground is .III) Calculate Following Problems:1. A wedge with mass M rests on a frictionless horizontal tabletop. A block with mass m is placed on the wedge, and a horizontal force F isapplied to the wedge. What must be the magnitude of F if the block is toremain at a constant height above the table top?2. The mass of blocks A and B in Figure are 20.0kg and 10.0kg, respectively.The blocks are initially at rest on the floor and are connected by a masslessstring passing over a massless and frictionless pulley. An upward force F isapplied to the pulley. Find the accelerations a1 of block A and a2 of block Bwhen F is(a) 124N ; (b) 294N ; (c) 424N.3. An object is drop from rest. Find the function of speed with respect to timeand the terminal speed. Assuming that the drag force2is given by D = bv .4. A small bead can slide without friction on a circular hoop that is ina vertical plane and has a radius of 0.100m. The hoop rotates at aconstant rate of 4.00rev/s about a vertical diameter.(a) Find the angleβ at which the bead is in vertical equilibrium.(b) Is it possible for the bead to “ride” at the same elevation as thecenter of the hoop?(c) What will happen if the hoop rotates at 1.00rev/s.Chapter 3 Linear momentum, Conservation of momentumI)Choose one correct answer among following choices1.An object is moving in a circle at constant speedv . The magnitude of the rate of change of momentum of the object23A.is zero.B. is proportional to v.C. is proportional to v .D. is proportional to v .2.If the net force acting on a body is constant, what can we conclude about its momentum?A. The magnitude and/or the direction of P may change.B.The magnitude of P r remains fixed, but its direction may change.C.The direction of P remains fixed, but its magnitude may change.D.P remains fixed in both magnitude and direction.3.If I is the impulse of a particular force, what is dI /dt ?A. The momentumB. The change in momentumC.The forceD. The change in the force4. A variable force acts on an object from t i 0 to t f . The impulse of the force is zero. One can conclude thatA. r 0 and P 0.B. r 0 but possibly P 0.C. possibly r 0 but P 0.D. possibly r 0 and possibly P 0.5. A system of N particles is free from any external forces. Which of the following is true for the magnitude of the total momentum of the system?A. It must be zero.B. It could be non-zero, but it must be constant.C. It could be non-zero, and it might not be constant.D.The answer depends on the nature of the internal forces in thesystem.6.The x and y coordinates of the center of mass of the three-particle system shown below are:A. 0, 0B. 1.3m, 1.7mC. 1.4m, 1.9mD. 1.9m, 2.5m7.Block A, with a mass of 4 kg, is moving with a speed of 2.0m/swhile block B, with a mass of 8 kg, is moving in the oppositedirection with a speed of 3m/s. The center of mass ofthe two block-system is moving with a velocity of:A. 1.3m/s in the same direction as A.B.1.3m/s in the same direction as B.C.2.7m/s in the same direction as A.D.1.0m/s in the same direction as B.8. A large wedge with mass of 10kg rests on a horizontal frictionless surface, as shown. A block with a mass of 5.0kg starts from rest and slides down the inclined surface of the wedge, which is rough. At one instant the vertical component of the block 's velocity is 3.0m/s and the horizontal component is 6.0m/s. At that instant the velocity of the wedge is:A. 3.0m/s to the leftB. 3.0m/s to the rightC. 6.0m/s to the rightD. 6.0m/s to the left9. A 1.0-kg ball moving at 2.0m/s perpendicular to a wall rebounds from the wall at1.5m/s. The change in the momentum of the ball is:A. zeroB. 0.5N s· away from wallC. 0.5N s· toward wallD. 3.5N s· away from wallII)Fill in the empty space with correct answer1.Two objects, A and B, collide(碰撞). A has a mass of m A 2kg , and B has a mass of m B4kg. The velocities before the collision are v A (2i 3j)m/s and v B (4i 2j)m/s. After the collision, v A (3i 2 j ) m/s. The final velocity of Bv B m/s.2. A stream of water impinges on(撞击) a stationary “dished”turbine blade, as shown in Fig.8. The speed of the water is v, bothbefore and after it strikes the curved surface of the blade, and themass of water striking the blade per unit time is constant at thevalue dm/dt . The force exerted by the water on theblade is ______________ .o3. A 320g ball with a speed v of 6.22m/s strikes a wall at angle θ of 30.0o and then rebounds with the same speed and angle. It is in contact with the wall for 10.4 ms.(a)The impulse was experienced by the wall is .(b)The average force exerted by the ball on the wall is .4.The muzzle speed of a bullet can be determined using a device calleda ballistic pendulum, shown in Figure. A bullet of mass m moving atspeed v encounters a large mass M hanging vertically as a pendulum atrest. The mass M absorbs the bullet. The hanging mass (now consisting ofM + m) then swings to some height h above the initial position of thependulum as shown. The initial speed v′ of the pendulum (with theembedded bullet) after impact is . The muzzlespeedv of the bullet is .III)Calculate Following Problems:1. A block of mass m 1=1.60kg initially moving to the right with a speed of 4.00 m/s on a frictionless horizontal track collides with a spring attached to a second block of massm2=2.10kg initially moving to the left with a speed of 2.50 m/s, as shown in Figure. The spring constant is 600 N/m.(a) At the instant block 1 is moving to the right with a speed of 3.00 m/s, as in Figure, determine the velocity of block 2.(b) Determine the distance the spring is compressed at that instant.Chapter 4 Work and EnergyI) Choose one correct answer among following choices1. The work done by gravity during the descent of a projectile:A. is positiveB. is negativeC. is zeroD. depends for its sign on the direction of the y axis2. A particle has a constant kinetic energyE k . Which of the following quantities must also be constant? ( )(A) r (B) v (C) v (D) P3. A 0.2kg block slides (滑行) across a frictionless floor with a speed of 10m /s. Thenet work done on the block is ( )(A) -20J (B) -10J (C) 0J (D) 20J4. A 0.50kg object moves in a horizontal circular track with a radius of 2.5m. An external force of 3.0N, always tangent to the track, causes the object to speed up as it goesaround. The work done by the external force as the mass makes one revolution is:A. 24 JB. 47 JC. 59 JD. 94 J2. A3.00-kg steel ball strikes a wall with a speed of 10.0m/s at an angle of 60.0 with t °he surface. It bounces offwith the same speed and angle. If the ball is in contact withthe wall for 0.200 s, what is the average force exerted onthe ball by the wall?3. A small ball with mass m is released from rest at the top of a container which inside wall is semicircle-shapedand frictionless. The container with mass M and radius horizontal surface, as shown. When the ball slides to point B at the bottom of thecontainer, find the normal force exerted by the container on the ball.R rests on a frictionless5. A man pushes an 80-N crate a distance of 5.0m upward along a frictionless slope that makes an angle of 30? with the horizontal. His force is parallel to the slope. If the 2speed of the crate decreases at a rate of 1.5m,/ sthen the work done by the man is: A. -200 J B. 61 J C. 140 J D. 200 J6.When a certain rubber band is stretched a distance x, it exerts a restoring force of 2 magnitude F = ax+bx , where a and b are constants. The work done in stretching this rubber band from x = 0 to x = L is:2 3 2 2 3A. aL2 + bLx3B. aL + 2bL2C. a + 2bLD. aL2/2 +bL3/37.An ideal spring is hung vertically from the ceiling. When a 2.0-kg mass hangs at rest from it the spring is extended 6.0cm from its relaxed length. A downward external force is now applied to the mass to extend the spring an additional 10cm. While the spring is being extended by the force, the work done by the spring is: A. -3.6J B. -3.3J C. 3.6 J D. 3.3J8.Two objects with masses of m1 and m2 have the same kinetic energy and are both moving to the right. The same constant force F is applied to the left to both masses. If m1 = 4m2, the ratio of the stopping distance of m1 to that of m2 is:A. 1:4B. 4:1C. 1:2D. 1:19.At time t = 0 a 2-kg particle has a velocity of (4m/s) i - (3m/s) j . At t = 3s its velocity is (2m/s) i + (3m/s) j . During this time the work done on it was:A. 4 JB. -4JC. -12 JD. -40 J10. A 2-kg block starts from rest on a rough inclined plane that makes an angle of 6o0 with the horizontal. The coefficient of kinetic friction is 0.25. As the block goes 2.0m down the plane, the mechanical energy of the Earth-block system changes by: A. 0 B. -9.8J C.9.8J D. - 4.9 JII)Fill in the empty space with correct answer1. A chain(链条) is held on a frictionless table with one-fourth ofits length hanging over the edge, as shown in figure. If the chainhas a lengthL and a massm , the work required to pull the hangingpart back on the table is J.2. A 0.1kg block is dropped from a height of 2m onto a spring offorce constant k = 2N/m, as shown. The maximum distance thespring will be compressed is ____________ m . (g=10m/2s)3. A single constant force F 3i 5j N acts on a4.00-kg particle.(a) If the particle moves from the origin to the point having the vector position r 2i 3j m, the work down by this force is .(b) If its speed at the origin is 4.00 m/s, the speed of the particle at r is .(c)The change in the potential energy of the system isIII)Calculate Following Problems:1. A 3.00-kg mass starts from rest and slides a distance d down africtionless 30.0 incline°. While sliding, it comes into contact withan unstressed spring of negligible mass, as shown. The mass slidesan additional 0.200 m as it is brought momentarily to rest bycompression of the spring (k=400N/m). Find the initial separation d between the mass and thespring.2.Two masses are connected by a light string passing over a light frictionless pulley as shown. The 5.00-kg mass is released from rest.(a)Determine the speed of the 3.00-kg mass just as the 5.00-kg mass hits the ground.(b)Find the maximum height to which the 3.00-kg mass rises.Chapter 5 Angular momentum and Rigid bodyI)Choose one correct answer among following choices1. A particle moves with position given by r 3ti 4j , where r is measured in meters when t is measured in seconds. For each of the following, consider only t > 0. The magnitude of the angular momentum of this particle about the origin is A. increasing in time. B. constant in time. C. decreasing in time. D. undefined2. A solid object is rotating freely without experiencing any external torques. In this caseA. Both the angular momentum and angular velocity have constant direction.B.The direction of angular momentum is constant but the direction of the angular velocity might not be constant.C.The direction of angular velocity is constant but the direction of the angular momentum might not be constant.D.Neither the angular momentum nor the angular velocity necessarily has a constant direction.3. A 2.0-kg block travels around a 0.50-m radius circle with an angular velocity of 12 rad/s. The magnitude of its angular momentum about the center of the circle is:2 2 2 2 2A. 6.0kg m·2/sB. 12 kg m·2/sC. 48 kg/m2· sD. 72 kg m·2/s24. A 6.0-kg particle moves to the right at 4.0m/s as shown. Themagnitude of its angular momentum about the point O is:22A. zeroB. 288 kg·m /sC. 144 kg·m /sD.24kg·m2/s5.Two objects are moving in the x, y plane as shown. Themagnitude of their total angular momentum (aboutthe origin O) is:A. zeroB. 6kg m·2/sC. 12kg m·2/sD. 30kg m·2/s6. A 2.0-kg block starts from rest on the positive x axis 3.0m from the origin and2thereafter has a constant acceleration given by a 4i 3j(m/s2). At the end of 2s itsangular momentum about the origin is:2 2 2A. 0B. (-36 kg ·2/sm) kC. (+48 kg m·2/s) kD. (-96 kg ·2/sm)k7.As a 2.0-kg block travels around a 0.50-m radius circle it has an angular speed of12rad/s. The circle is parallel to the xy plane and is centered on the z axis, a distance of 0.75m from the origin. The z component of the angular momentum around the origin is:2 2 2 2A. 6.0kg m·2/sB. 9.0kg m·2/sC. 11kg m·2/sD. 14kg m·2/sII)Fill in the empty space with correct answer1. A particle located at the position vector r (2i j) m is acted by a forceF (i 3j)N. The torque about the origin should be _______________ N m.2.The velocity of a m=2kg body moving in the xy plane is given by v (i 2j) m/s.Its position vector is r (2i j)m. Its angular momentum L about the origin shouldbe _____________ kg m2s.3.Two particles each of mass m and speed v, travel inopposite directions along parallel lines separated by a distanced. The total angular momentum of the system about any originis .4. A particle is located at r = (0.5m) i + (-0.3m) j + (0.8m) k . A constant force ofmagnitude 2N acts on the particle. When the force acts in the positive x direction, the components of the torque about the origin is , and when the force acts in the negative x direction, the components of the torque about the origin is .5. A uniform beam of length l is in a vertical position with its lower end on a rough surface that prevents this end from slipping. The beam topples. At the instant before impact with the floor, the angular speed of the beam about its fixed end is .6. A disk of mass m and radius R is free to turn about a fixed, horizontal axle. Thedisk has an ideal string wrapped around its periphery from which another mass m (equal to the mass of the disk) is suspended, as indicated in Figure. Themagnitude of the acceleration of the falling mass is , the magnitude of theangular acceleration of the disk is .III)Calculate Following Problems:21.The pulley has radius 0.160m and moment of inertia 0.480kg·m . The rope does not slip on the pulley rim. Use energy methods to calculate the speed of the 4.00-kg block just before it strikes the floor.2. A block with mass m slides down a surface inclined 30 to the horizontal. The coefficient of kinetic friction is μ. A string attached to the block is wrapped around a wheel on a fixed axis. The wheel has massm and radius R with respect to the axis of rotation. The string pulls without slipping.a) What is the acceleration of the block down the plane? b)What is the tension in the string?3. A wooden block of mass M resting on a frictionless horizontal surface is attachedto a rigid rod of length l and of negligible mass. The rod is pivotedat the other end. A bullet of mass m traveling parallel to thehorizontal surface and normal to the rod with speedv hits the blockand becomes embedded in it. What is the angular momentum ofthe bullet–block system?Chapter 9 Mechanic oscillationI)Choose one correct answer among following choices1. A particle on a spring executes simple harmonic motion. If the mass of the particle and the amplitude are both doubled then the period of oscillation will change by a factor ofA. 4.B. 8.C. 2.D. 22. A particle is in simple harmonic motion with amplitude A. At time t=0 it is at x=-A/2 and is moving in the negative direction, then the initial phase is:A. 2π3/ radB. 4π3/ radC. π radD. 3 π /2 rad3. A particle is in simple harmonic motion with period T. At time t = 0 it is at the equilibrium point. Of the following times, at which time is it furthest from the equilibrium point?A. 0.5TB. 0.7TC. TD. 1.4T4. A weight suspended from an ideal spring oscillates up and down with a period T. If the amplitude of the oscillation is doubled, the period will be:A. TB. 2TC. T/2D. 4T5.The displacement of an object oscillating on a spring is given by x(t) = A cos( ω t + φ). If the initial displacement is zero and the initial velocity is in the negative x direction, then the phasec onstant φ is:A. 0B. π /2 radC. π radD. 3 π/2 rad6.An object is undergoing simple harmonic motion with period T, amplitude A and1initial phase . Its graph of x versus t is:7.An object of mass m, oscillating on the end of a spring with spring constant k, has amplitude A. Its maximum speed is:A. A k /mB. A2k/mC. A m/ kD. Am/kII)Fill in the empty space with correct answer1. The total energy of a s imple harmonic oscillato(r谐振子) with amplitude A and force constant k is _________________ .2. Find the initial phases(初相) of the simple harmonic motion as shown in figure.12III)Calculate Following Problems:1. An object oscillates with simple harmonic motion along the x axis. Its displacement from the origin varies with time according to the equation: x (4.00m)cos( t 4 ). where t is in seconds and the angles in the parentheses are in radians.(a) Determine the amplitude, frequency, and period of the motion.(b) Calculate the velocity and acceleration of the object at any time t.(c)Determine the maximum speed and maximum acceleration of the object.2. A 50.0-g mass connected to a spring with a force constant of 35.0 N/m oscillates on a horizontal, frictionless surface with amplitude of 4.00 cm.Find (a) the total energy of the system and (b) the speed of the mass when the displacement is 1.00cm.Find (c) the kinetic energy and (d) the potential energy when the displacement is 3.00cm.Chapter 10 WavesI) Choose one correct answer among following choices1. Let f be the frequency, v the speed, and T the period of a sinusoidal traveling wave. The correct relationship is:A. f = 1/TB. f = v + TC. f = vTD. f = v/T2. Water waves in the sea are observed to have a wavelength of 300m and a frequency of0.07 Hz. The speed of these waves is:A. 0.00021m/sB. 2.1m/sC. 21m/sD. 210m/s3.The transverse wave shown is traveling from left to right in a medium. The direction of the instantaneous velocity of the medium at point P is:A. upward。