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1. The cheetah can run as fast as 100 km/h, the sailfish can swim as fast as 120 km/h, and the

falcon can fly as fast as 250 km/h. The three of them take part in a relay with each covering

a distanceLat maximum speed. The average speedof this triathlon team

a) cannot be determined sinceLhas not been specified.

b) is 120 km/h.

c)

is approximately 157 km/h.d) is approximately 134 km/h.

e)

is approximately 78 km/h.

2. Two blocks with masses 1M and 2M , such that 21 MM , are placed in contact with each

other on a frictionless, level surface. We can apply a constant horizontal force Feither

from the left orfrom the right, as shown in Figure 1.

Figure 1

The contact forcesbetween the blocks are

a) zero.

b) the same in either case.

c) larger when Fis applied from the left.

d) larger when Fis applied from the right.

e)

impossible to determine based on this data.

3.

An elevator supported by a single cable descends a shaft at a constant speed. The only

forces acting on the elevator are the tension in the cable and the gravitational force. Which

one of the following statements is true?

a) The work done by the tension force is zero.

b) The net work done by the two forces is zero.

c) The work done by the gravitational force is zero.

d) The magnitude of the work done by the gravitational force is larger than that done by

the tension force.

e) The magnitude of the work done by the tension force is larger than that done by the

gravitational force.

4. A roadway for motor racing is designed for race cars moving at a speed of 40 m/s. A curved

section of the roadway is a circular arc of radius 230 m. This section is banked so that a

race car can go around the curve without friction. At what angle is it banked?

a) 29

b) 31

c) 33

d)

35

e)

37

1M 2M

F 1M 2M

F

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5. A block is dropped from a high tower and is falling freely under the influence of gravity.

Neglect air resistance. Which one of the following statements is true concerning this

situation?

a) The kinetic energy increases by equal amounts over equal distances.

b) The kinetic energy of the block increases by equal amounts in equal times.

c)

The potential energy of the block decreases by equal amounts in equal times.d) The total energy of the block increases by equal amounts over equal distances.

e)

As the block falls, the net work done by all of the forces acting on the block is zero.

6. Two children,AandB, are playing on two trampolinesas shown in Figure 2.

Figure 2

ChildAcan bounce up to one-and-a-half times higherthan childB. The initial speed up of

childBis 5.00 m/s. How long was childAin the air?

a) 1.53 s

b)

1.25 s

c)

1.02 sd) 0.625 s

e) 0.510 s

7. Two boxes are connected to each other as shown in Figure 3.

Figure 3

The system is released from rest and the 1.00-kg box falls through a distance of 1.00 m.

The surface of the table is frictionless. What is the kinetic energyof box B just before it

reaches the floor?

a)2.45 J

b)4.90 J

c)9.80 J

d)

29.4 Je)39.2 J

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8. Neglect air resistance. If the bullet leaves a gun at a speed of 145 m/s, at what angle shouldthe gun be aimed so a target (on the same level) 65.0 m away will be hit?

a) 0.45

b) 6.26

c) 1.24

d)

74.1

e) 868.0

9. A cart is being pushed down an incline with a force F, as shown in Figure 4.

Figure 4

The coefficient of kinetic friction between the cart and the incline isk

. If the cart

accelerates down the incline with acceleration ga , the force Fis given by

a) Mg .

b)

Mgk )sincos1( .c) Mgk )sincos1( .

d) Mgk )cossin1( .

e) Mgk

)cossin1( .

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10.The speed of a car moving along a level circular track of radius 50 m is increased uniformly

in time. When the car is East of the centre, its total acceleration is 2sm10 at 37 West of

North, as shown in Figure 5.

Figure 5

How long does it take to return to the same point?a) 7.0 s

b) 9.0 sc) 11 sd) 14 se) 18 s

11.Consider two blocks, of masses kg71 m and kg52 m , hung by a massless string from

a frictionless pulley as shown in Figure 6.

Figure 6

The bottoms of the blocks are 20 meters above the top of a horizontal table. When they arereleased from rest, how many seconds will it take for one of the blocks to hit the table?a) 6

b) 5c) 4d) 3e) 2

North

South

EastWest

37

2sm10

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12.A dart is loaded into a spring-loaded toy dart gun by pushing the spring in by a distance d.

For the next loading, the spring is compressed by a distance 2d. How much faster does the

second dart leave the gun compared to the first?

a) Half as fast.

b) Four times as fast.

c)

The same.d) One-fourth as fast.

e)

Two times as fast.

13.BlockA, of mass 5.0 kg, and block Xare attached to a rope that passes over a light and

frictionless pulley, as shown in Figure 7.

Figure 7

An 80-N force P is applied horizontally to block A, keeping it in contact with a rough

vertical wall. The coefficients of static and kinetic friction between the wall and blockA

are 40.0s and 30.0k respectively. The mass of blockXis adjusted until blockA

moves upwardwith an acceleration of2

1.6 m/s . What is the mass of blockX?a) 9.9 kg

b)

9.3 kg

c) 8.7 kg

d) 8.1 kg

e) 7.5 kg

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14.A ball is fixed to the end of a string, which is attached to the ceiling at point P. As shown

in Figure 8, the ball is projected downward at A with the launch speed 0v . Travelling on a

circular path, the ball comes to a halt at point B.

Figure 8

Ignore air resistance and friction. What enables the ball to reach point B, which is above

point A?

a)

The ball's initial gravitational potential energy.

b)

The work done by the tension in the string.c) The work done by the gravitational force.

d) The ball's initial kinetic energy.

e) None of the above.

15.The positionx(in m) of a race car on a straight track at time t(in s) is given as

dctbtattx 23)( ,

where a, b, c, and d are some constants. What is the average acceleration (in 2sm )

between time s0.41 t and s0.92 t ?

a) 133a+ 13b+ 1.0c

b)

54a+ 2.0bc) 39a+ 2.0b

d)

24a+ 2.0b

e) 15a

16.A book of mass mis projected with a speed vacross a horizontal surface. The book slides

until it stops due to the friction between the book and the surface. The surface is now tilted

at an angle )900( with respect to the horizontal, and the book is projected up the

surface with the same initial speed v. When the book has come to rest, how does the

decrease in mechanical energy of the book - Earth systemcompare with that when the book

slid over the horizontal surface?

a)

Its the same.

b) Its larger on the tilted surface.

c)

Its smaller on the tilted surface.

d) It can be larger or smaller, depending on the value of .

e)

It can be larger or smaller, depending on the coefficient of kinetic friction between the

book and the surface.

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17.A flying saucer is moving with constant acceleration. At an earlier time 1t , it was observed

to have position vector 01 r

and velocity vector sm)200(1 jv

. At a later time 2t , it

has position vector m)10002000(2 jir

and velocity vector sm)100200(2 jiv

.

The saucers acceleration

a)

is given by 2sm)3020( jia

.

b) is given by 2sm)3020( jia

.

c) is given by 2sm)1510( jia

.

d) is given by 2sm)1510( jia

.

e) cannot be determined since 1t and 2t have not been specified.

18.A block with mass mis being pushed by a constant force Fthat makes an angle of withthe horizontal, as shown in Figure 9.

Figure 9

The coefficient of kinetic friction between the block and the surface isk

. If the block

moves with constant velocity on a level surface, which one of the following equations givesthe correct magnitude of F?

a)

sin

mgF k

b)

tan

mgF k

c) cosmgF k

d)

sincosk

kmg

F

e)

sincos k

kmg

F

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19.Two wooden blocks,AandB, each of mass 0.30 kg are connected by a string that passes

over a light, frictionless pulley. BlockAslides on a horizontal table, while blockBhangs

suspended by the string, as shown in Figure 10.

Figure 10

At time 0t , blockBis 0.80 m over the floor, and two blocks are released from rest. After

2.5 s, blockBreaches the floor. What is the coefficient of kinetic friction between the table

and blockA?

a) 0.35

b) 0.52

c)

0.65

d) 0.84

e)

0.95

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20.A child slides without friction from a height halong a curved water slide as shown in Figure

11.

Figure 11

She is launched from a height 5h into the pool. Determine her maximum airborne height

yin terms of hand .

a) 5)cos41( 2 h

b)

5)sin41( 2 h

c) 5)cos21( 2 h

d) 5)sin21( 2 h

e)

5)tan41(2

h

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