Physics Final Exam Review

A projectile is launched with an initial velocity of 80 m/s at an angle of 30° above the horizontal. Neglecting air resistance, what is horizontal component of the projectile's acceleration?

0 m/s^2

A projectile is launched with an initial velocity of 80 m/s at an angle of 30° above the horizontal. Neglecting air resistance, what is the horizontal component of the projectile's acceleration?

0 m/s^2

A catcher stops a ball traveling at 40 m/s in a distance of 20 cm and feels a resultant force 600 N against her glove. What is the mass of the ball?

0.15 kg

A child pulls a 3.00-kg sled across level ground at a constant velocity with a light rope that makes an angle of 30.0° above horizontal. The tension in the rope is 5.00 N. Assuming the acceleration due to gravity is 9.81 m/s2 , what is the coefficient of friction between the sled and the ground?

0.161

A jumper in the long-jump goes into the jump with a speed of 12 m/s at an angle of 20° above the horizontal. How long is the jumper in the air before returning to the Earth?

0.84 seconds

At the same moment, one rock is dropped and one is thrown downward with an initial velocity of 10 m/s from the top of a 300 m building. How much earlier does the thrown rock strike the ground?

0.95 seconds

A typical E. coli bacterium is measured in microns. Which of the following is a representation of a micron?

1*10^-6

How long does it take far a train traveling 60.4 miles per hour to travel 81 miles? Be sure to use the appropriate number of significant fiqures?

1.3 hours

An object is thrown upwards with a speed of 14.0 m/s. How long does it take it to reach its maximum height?

1.43 seconds

An object is thrown upwards with a speed of 14 m/s. How high above the projection point does it reach?

10 m

An object is thrown upwards with a speed of 14 m/s. How high above the projection point does it reach?

10 m

A car is moving with a speed of 32.0 m/s. The driver sees an accident ahead and slams on the brakes, giving the car a deceleration of 3.50 m/s2. How far does the car travel after the driver put on the brakes before it comes to a stop?

10.5 seconds

A train travels at a constant speed of 60.4 miles per hour for 101.5 minutes. What distance does the train cover?

102 miles

A projectile is shot from the edge of a vertical cliff 60.0 m above the ocean. It has a speed of 100 m/s and is fired at an angle of 35.0° above the horizontal. How far from the foot of the vertical cliff does the projectile hit the water?

1040 m

How many cm^2 equal m^2?

10^4

Which one of the following is the longest length?

10^4 millimeters

A hockey puck slides off the edge of a table with an initial velocity of 20.0 m/s. The height of the table above the ground is 2.00 m. How far from the edge of the table, measured along the floor, does the puck hit the floor?

12.8 m

A vector has components Ax = 12 m and Ay = 5.0 m. What is the magnitude of vector

13 m

A car is traveling with a constant speed when the driver suddenly applies the brakes, giving the car a deceleration of 3.50 m/s^2. If the car comes to a stop in a distance of 30.0 m, what was the car's original speed?

14.5 m/s

A car is moving with a speed of 32.0 m/s. The driver sees an accident ahead and slams on the brakes, giving the car a deceleration of 3.50 m/s2. How far does the car travel after the driver put on the brakes before it comes to a stop?

146 m

A car is moving with a speed of 32.0 m/s. The driver sees an accident ahead and slams on the brakes, giving the car a deceleration of 3.50 m/s2. How far does the car travel after the driver put on the brakes before it comes to a stop?

146 m

A plane is headed eastward at a speed of 156 m/s. A 20.0 m/s wind is blowing southward at the same time as the plane is flying. The velocity of the plane relative to the ground is

157 m/s at an angle 7.31 south of east

A boy jumps at a speed of 20.0 m/s at an angle 25 degrees above the horizontal. What is the horizontal component of the boy's velocity?

18.1 m/s

A boy jumps at a speed of 20.0 m/s at an angle 25.0 degrees above the horizontal. What is the horizontal component of the boys velocity?

18.1 m/s

A boy jumps at a speed of 20.0 m/s at an angle of 25.0° above the horizontal. What is the horizontal component of the boy's velocity?

18.1 m/s

A car is traveling at 26.0 m/s when the driver suddenly applies the brakes, giving the car a constant decceleration. The car comes to a stop in a distance of 120.0 m. How fast was the car moving when it was 60.0 m past the point where the brakes were applied?

18.4 m/s

Vector = 6.0 m and points 30° north of east. Vector = 4.0 m and points 30° south of west. The resultant vector + is given by

2.0 m at an angle 30° north of east.

What is the conversion factor between km/h and m/s?

2.78*10^-1 m/s

To determine the height of a bridge above the water, a person drops a stone and measures the time it takes for it to hit the water. If the height of the bridge is 41 m, how long will it take for the stone to hit the water?

2.9 seconds

A vector A has components Ax+12.m and Ay=5.0 m. what is the angle that vector A makes with the x-axis?

22.6 degrees

A vector A has components Ax=12.0 m and Ay=5.0 m. What is the angle that vector A makes with the X-axis?

22.6 degrees

To determine the height of a bridge above the water, a person drops a stone and measures the time it takes for it to hit the water. If the time is 2.3 s, what is the height of the bridge?

26 m

To determine the height of a bridge above the water, a person drops a stone and measures the time it takes for it to hit the water. If the time is 2.3 s, what is the height of the bridge?

26 m

In the year 2000, the average size of a transistor in a microprocessor was 250 nanometers. A human hair has a diameter of 70 microns (micrometers). How many transistors fit across a human hair?

280

The figure represents the position of a particle as it travels along the x-axis. At what value of t is the speed of the particle equal to zero?

3 seconds

The minimum takeoff speed for a certain airplane is 75 m/s. What minimum acceleration is required if the plane must leave a runway of length 950 m? Assume the plane starts from rest at one end of the runway

3.0 m/s^2

A ball is launched horizontally at a speed of 23.4 m/s from the roof of a building 55.0 m tall. Determine the time for the ball to reach the ground and the speed of the ball just before it strikes the ground.

3.35 s, 40.3 m/s

A ball is thrown horizontally from a 19 m-high building with a speed of 2.0 m/s. How far from the base of the building does the ball hit the ground?

3.9 m

A car is moving with a constant accerleration. At t=5.0 s its velocity is 8.0 m/s and at t=8.0 s its velocity is 12.0 m/s. What is the distance traveled in that interval of time?

30 m

A car is movingwith a constant acceleration. At t= 5.0 s its velocity is 8.0 m/s and at t = 8.0 s its velocity is 12 m/s. What is the distance traveled in that interval of time?

30 m

A bullet is fired from ground level with a speed of 150 m/s at an angle 30.0° above the horizontal at a location where g = 10.0 m/s2. What is the vertical component of its velocity after

35 m/s

A heavy rock is dropped from rest at the top of a cliff and falls 100 m before hitting the ground. How long does the rock take to fall to the grouns and what is its velocity just before it hits?

4.5 seconds, and 44.3 m/s

A heavy rock is dropped from rest at the top of a cliff and falls 100 m before hitting the ground. How long does the rock take to fall to the ground and what is its velocity just before it hits?

4.51 seconds and 44.3 m/s

Vector M = 4.00 m points eastward and vector N = 3.00 m points northward. The resultant vector M + N is given by

5.0 m at an angle 71.6 north of east

A boy throws a ball with an initial velocity of 25 m/s at an angle of 30° above the horizontal. How high above the projection point is the ball after 2.0 s?

5.4 m

Vector has a magnitude of 16.0 m and is pointing eastward. It is rotated 110.0° clockwise. The component of this vector along west is

5.47 m

Four students measure the mass of an object, each using a different scale. They record their results as follows: Which student used the least precise scale?

50 grams

Jane has a mass of 50 kilogrmas. Express her mass in grams and hectograms

50,000 g and 500 hg

An 8.0 kg object is being acted upon by gravity as well as two other forces as shown in the figure below. The result is that the object moves with constant velocity. Which of the following relationships is implied by Newton's 2nd Law, for the y-component of motion?

6.0 sin55° + 5.0 sin25° - 8.0 g cos20=0

Vector A = 6.0 m and points 40° south of east. Vector B = 4.0 m and points 50° west of south. The resultant vector A + B is given by

6.6 m at an angle 13° east of south.

You drive 6.00 km at 50.0 km/h and then another 6.00 km at 90.0 km/h. Your average speed over the 12.0 km drive will be

63 km/h

Vector A= 6.0 m and points 30 degrees north of east. Vector B = 4.0m and points 30 degrees west of north. The resultant vector A+B is given by

7.2 m at an angle 26 degrees east of north

Vector A=6.0 m and points 30 degrees south of east. Vector B=4.0 m and points 30 degrees west of south. The resultant vector A+B is given by

7.2 m at an angle 64 degrees south of east

A child throws a ball with an initial speed of 8.00 m/s at an angle of 40.0° above the horizontal. The ball leaves her hand 1.00 m above the ground. How far from where the child is standing does the ball hit the ground?

7.46 m

A projectile is shot from the edge of a vertical cliff 60.0 m above the ocean. It has a speed of 100 m/s and is fired at an angle of 35.0° below the horizontal. How far from the foot of the vertical cliff does the projectile hit the water?

79.1 m

A jumper in the long-jump goes into the jump with a speed of 12 m/s at an angle of 20° above the horizontal. How far does the jumper jump?

9.4 m

A stone is thrown straight up. What is its acceleration at the highest point?

9.8 m/s^2 downward

An airplane starts from rest and accelerated at 10.8 m/s^2. What is its speed at the end of a 400 m long runway?

93.0 m/s

A pepperoni pizza has 2.8 megacalories. Juan eats exactly 1/3 of the pizza. How many kilocalories has he consumed?

933 kcal

A hockey puck is acted on by various forces, as shown in the figure below. How does the magnitude of the puck's acceleration compare in each case?

Aa < Ad < Ab < Ac

The mass of an object A is four times of that of object B. An external force is applied to move these objects and the force applied on object B is half of that applied on object A. What is the ratio of accelerations of these objects?

Aa/Ab=1/2

A child is sledding down an inclined plane of concrete which is making an angle θ above the horizontal as shown in the figure below. Which of the following free body diagrams is correctly representing forces acting on him?

Answer D

Under which of the following conditions would a car have a westward acceleration?

As a car travels eastward with its velocity is decreasing

The components of vectors A and B are ( B 30 degrees in quadrant 2, A 90 degrees in quadrant 1)

Ax=Acos0 Bx=-Bcos60 Ay=Acos90 By=Bcos30

A ball is tied to a string, which is maintained in a circular path at a constant speed. What would be the centripetal acceleration acting on the ball if the speed is doubled and length of the string is reduced to half?

Centripetal acceleration will be eight times of the initial value

A roller coaster is on a track that forms a vertical (circular) loop. If the coaster maintains contact with the track as it passes by the top of the loop, how must the centripetal force and the weight be related at that instant?

Greater than or equal to the weight of the car, pointing downward

A constant (non-zero) net force acts on an object. Which of the following best describes the motion of the object?

It has a constant non-zero acceleration

Vector T as expressed in terms of vectors M and N is given by

M+N

A lamp of mass m is hanging motionless from a rope tied to the ceiling. What is the tension T in the rope?

T=mg

A car is moving towards east at a constant speed of 40 mph. Upon approaching the red light, the car decelerates and comes to a stop. What is the direction of acceleration and the frictional force acting on the car before it comes to a stop?

The acceleration and frictional force both point west.

Suppose that a car traveling to the East (+x direction) begins to slow down as it approaches a traffic light. Make a statement concerning its acceleration

The car is decelerating, and its acceleration is negative.

Suppose that an object travels from one point in space to another. How does the displacement and the distance travel compare?

The displacement is less than or equal to the distance traveled

A projectile is launched with initial speed v 0 at an angle of 30° above the horizontal on a level ground. If a second projectile is launched with the same initial speed but at an angle of 60° above the horizontal, then which of the following statement is true:

The ranges of the two projectiles will be identical.

Three forces F1 = F2 + F3 =70 N are acting on an object at the origin as shown in the figure?Which of the following statements is true regarding the resultant force acting over the object?

The resultant force is zero

Vectors M and N satisfy the equation M+N= 0. These vectors satisfy one of the following statements.

Vectors M and N have the same lengths.

A car travels east and its speed decreases. The acceleration of the car is in which of the following directions?

Westward

Is it possible to have a zero acceleration, and still be moving?

Yes

A vector quantity is defined as

a quantity that is specified by using both a numerical value and a direction

The slope of a line connecting two points on a position versus time graph gives

average velocity

The position x, of an object is given by the equation x=A+Bt+Ct^2, where t refers to time. What are the dimensions of A, B, and C?

distance, distance/time, distance/time^2

A car traveling with the velocity v is deceleration by a constant acceleration of magnitude a. It takes time t to come to rest. If its initial velocity were doubled, the time required to stop would

double as well

When adding several quantities, the number of decimal places in the result must always be

equal to the number of decimal places in the least accurate of the quantities.

When multiplying several quantities, the number of significant digits in the result must always be

equal to the number of significant digits in the least accurate of the quantities

The slope of a tangent line at a given time value on a position versus time graph gives

instantaneous velocity

If the initial speed of a projectile is doubled

its range will quadruple

If you are measuring the thickness of a strand of human hair, the most appropriate unit is the

micrometer

In the absence of an external force, a moving object will

move with constant velocity

If the velocity versus time graph of an object is a horizontal line, the object is

moving with constant non-zero speed

If the velocity versus time graph of an object is a horizontal line, the object is

moving with constant speed

A 47.0-kg person steps on a scale in an elevator. The scale reads 461 N. How is the elevator moving?

moving with constant velocity or at rest

A student kicks a soccer ball in a high arc toward the opponent's goal. At the highest point in its trajectory:

neither the ball's velocity nor its acceleration is zero

A car is traveling north at 17.7 m/s. After 12 s its velocity is 14.1 m/s in the same direction. Find the magnitude and direction of the car's average acceleration

o.30 m/s^2 South

A car traveling with the velocity v is decelerated by a constant acceleration of magnitude a. It travels a distance d before coming to rest. If its initial velocity were doubled, the distance required to stop would

quadruple

For general projectile motion, the vertical component of a projectile's acceleration

remains a non-zero constant

In solving a physics problem you end up with a fractions which has units of meters in the numerator and meters/second in the denomitor. The units for your answer are

seconds

A ball rolls off the edge of a table. The horizontal component of the ball's velocity remains constant during its entire trajectory because

the ball is not acted upon by a force in the horizontal direction.

A 20-ton truck collides with a 1500-lb car and causes a lot of damage to the car. Since a lot of damage is done on the car

the force on the truck is equal to the force on the car

A mountain climber encounters a crevasse in an ice field. The opposite side of the crevasse is a height h lower, and is separated horizontally by a distance w. To cross the crevasse, the climber gets a running start and jumps in the horizontal direction. If the height of the crevasse increases but the width remains the same, then,

the minimum speed needed to cross the crevasse decreases

Marcia uses a bow to shoot an arrow with initial velocity of magnitude v0 and at an angle θ above the horizontal. When the arrow returns to the same height from which it started,

the speed of the arrow is again v0.