physics final

350

A 0.5-kg ball moving at 5 m/s strikes a wall and rebounds in the opposite direction with a speed of 2 m/s. If the impulse occurs for a time duration of 0.01 s, then the average force (magnitude only) acting upon the ball is ______________ Newtons.

0.5

A 10-Newton object moves to the left at 1 m/s. Its kinetic energy is approximately ______________ Joules.

0.687 m/s

A 100-g toy car is propelled by a compressed spring that starts it moving. The car follows the curved track . Show that the final speed of the toy car is___ m/s, if its initial speed is 2.00 m/s and it coasts up the frictionless slope, gaining 0.180 m in altitude.

3

A 4 kg object has a momentum of 12 kg•m/s. The object's speed is ______________ m/s.

10

A 50-kg platform diver hits the water below with a kinetic energy of 5000 Joules. The height (relative to the water) from which the diver dove was approximately ______________ meters.

20 m/s

A ball is kicked with an initial velocity of 16 m/s in the horizontal direction and 12 m/s in the vertical direction. At what speed does the ball hit the ground?

0.072 m

A ball is rolled horizontally off a table with an initial speed of 0.24 m/s. A stop watch measures the ball's trajectory time from table to the floor to be 0.30 s. How far away from the table does the ball land? (g = 9.8 m/s^2) and air resistance is negligible)

.44 m

A ball is rolled horizontally off a table with an initial speed of 0.24 m/s. A stopwatch measures the ball's trajectory time from table to the floor to be 0.30 s. What is the height of the table? (g = 9.8m/s^2) and air resistance is negligible

0 m

A ball is thrown 5m straight up . It takes 0.2 s to return back to the start position. What is the ball displacement after that time ?

300

A baseball pitcher delivers a fast ball. During the throw, the speed of the ball increases from 0 to 30.0 m/s over a time of 0.100 seconds. The average acceleration of the baseball is ______________ m/s 2 2 .

the upstream trip

A boat moves through the water in a river at a speed of 8 m/s relative to the water. The boat makes a trip downstream and then makes a return trip upstream to the original starting place. Which trip takes longer?

1.02 N

A certain man has a mass of 80 kg and a density of 955 kg/m^3 (excluding the air in his lungs). Find the buoyant force air exerts on him. ( air density 129 kg m-3)

13500 kg

A cube-shaped block of pinewood has a surface area of 9 m² and a density of 0.5 g cm-3. Its mass equals

20.4 m

A fireman, stays away from a burning building, directs a stream of water from a fire hose at an angle of 30.0° above the horizontal. If the initial speed of the stream is 40.0 m/s, what is maximum height of the water

entirely vertical

A football is kicked into the air at an angle of 45 degrees with the horizontal. At the very top of the ball's path, its acceleration is? (ignore air resistance)

entirely horizontal

A football is kicked into the air at an angle of 45 degrees with the horizontal. At the very top of the ball's path, its velocity is?

he is moving with a constant speed (on average).

A fullback is running down the football field in a straight line. He starts at the 0-yard line at 0 seconds. At 1 second, he is on the 10-yard line; at 2 seconds, he is on the 20-yard line; at 3 seconds, he is on the 30-yard line; and at 4 seconds, he is on the 40-yard line. This is evidence that

Pascal's

A hydraulic press allow large masses to be lifted with small forces as a result of which principle?

20 N west

A person is pulling west with 35 N of force against a person pulling east with 15 N of force. What is the net force?

5000

A platform diver weighs 500 N. She steps off a diving board that is elevated to a height of 10 meters above the water. The diver will possess ______________ Joules of kinetic energy when she hits the water.

52.3 m

A powerful motorcycle can accelerate from rest to 26.8 m/s (100 km/h) in only 3.90 s. How far does it travel in that time?

200

A student adds two vectors with magnitudes of 200 and 40. Which one of the following is the closest possible choice for the magnitude of the resultant?

+5J

A system has 30 J of heat added to it and in doing so, it does 25 J of work. (work is done by the system) The change in internal energy will be:

doubled

A truck driving along a highway road has a large quantity of momentum. If it moves at the same speed but has twice as much mass, its momentum is ______________.

mass times acceleration

According to Newton's 2nd Law of Motion, force equals -

equal and opposite directions

According to Newton's Third Law, action and reaction are

100 km/h

An airplane moves at 141 km/h toward the northeast (45 degrees). What is its component velocity in the northward direction?

141 km/h

An airplane that flies at 100 km/h in a 100 km/h hurricane crosswind has a speed (relative to the ground) of?

50

An arrow is drawn back so that 50 Joules of potential energy is stored in the stretched bow and string. When released, the arrow will have a kinetic energy of ______________ Joules.

increase

An increase in the depth of water creates what kind of change in water pressure?

twice as much potential energy

An object is raised above the ground gaining a certain amount of potential energy. If the same object is raised twice as high it gains ______________.

true

An object's inertia depends on its mass.

speed increases

As an object speeds up uniformly , its ______________.

the same

As in the video "A bullet shoot vs bullet drop", the measurable times were

decrease

As you climb higher up a mountain, air pressure would:

it is the same throughout the path.

At what point in its path is the horizontal component of the velocity (Vx ) of a projectile the smallest?

twice that of car B

Car A has a mass of 1000 kg and a speed of 60 km/h, and car B has a mass of 2000 kg and a speed of 30 km/h. The kinetic energy of car A is ______________.

9.8m/s^2

Gravitational Acceleration "g" on the Earth has the magnitude of

3.6 megajoules

How many Joules of energy are in one kilowatt-hour?

180 N

How much force is needed to accelerate a 90 kg skier 2 m/s2 ?

0.058 m

How much taller does the Eiffel Tower become at the end of a day when the temperature has increased by 15°C? Its original height is 321 m and you can assume it is made of steel. (coefficient of extension for steel= 1.2 10^-5/ C)

3 J

How much work does a supermarket checkout attendant do on a can of soup he pushes 0.600 m horizontally with a force of 5.00 N? Express your answer in joules .

.5g/cm^3

If an object has a mass of 4 grams and a volume of 8 cubic centimeters, what would be its density?

changing velocity

If an object has an acceleration of 0 m/s^2, then one can be sure that the object is not ______________.

speed

If an object has kinetic energy, then it also must have ______________.

westward

If an object is moving eastward and slowing down, then the direction of its acceleration vector is ______________.

eastward

If an object is moving eastward and slowing down, then the direction of its velocity vector is ______________.

moving faster than car B, but not necessarily accelerating.

If car A passes car B, then car A must be ______________.

3 km

If it takes one minute for an airplane to reach speed 100 m/s from start to take -off . How long is the take- off path ( airplane displacement in that time) .

10 Newtons

If you push on a wall with a force of -10 Newtons, the force acting on you is

Less than 1 gram per cubic centimeter

In order for an object to float in a container of water its density must be:

work done by system

In the equation: change in U = Q - W , -W stands for ?

2.54 L

Mercury (density = 13.6 g/cm^3) commonly supplied in flasks containing 34.5 kg . What is the volume in mili-liters (mL) of this much mercury?

3.00 x 10^3

On takeoff, a rocket accelerates from rest at a rate of 50.0 m/s^2 for exactly 1 minute. The rocket's speed after this minute of steady acceleration will be ______________ m/s.

1 Newton of force per square meter

One Pascal is equal to:

C + A = B (only correct)

Referring to the following figure, the correct relation is:

her velocity has a leftward direction and her acceleration has a leftward direction.

Renatta Oyle is again found driving her '86 Yugo down Lake Avenue, leaving the following trail of oil drops on the pavement. If her car is moving from right to left, then ...

remains constant

Roll a bowling ball off the edge of a table. As it falls, its horizontal component of velocity

less

Salt water is more dense than fresh water. A ship floats in both fresh water and salt water. Compared to the fresh water, the amount of water displaced in the salt water is ______________

100 ATM

Some species of whales can dive to the depth of 1 kilometer. What is the total pressure they experience at this depth? (Density = 1020 kg m-3 and 100 000 N/m2= 1 ATM.)

588 N

Suppose a 60.0-kg gymnast climbs a rope. What is the tension in the rope if he climbs at a constant speed?

0.13m/s^2 in the direction of 2nd child push

Suppose two children push horizontally, but in exactly opposite directions, on a third child in a wagon. The first child exerts a force of 75.0 N, the second a force of 90.0 N, friction is 12.0 N, and the mass of the third child plus wagon is 23.0 kg. What would be the acceleration ?

60 km/h.

Suppose you take a trip that covers 180 km and takes 3 hours to make. Your average speed is

0 N

The amount of net force required to keep a 5-kg object moving rightward with a constant velocity of 2 m/s is ______________.

20 km/hr

The average speed of an object which moves 10 kilometers (km) in 30 minutes is ______________.

10.0 m/s

The distance-time graph represents the position of an object moving in a straight line. What is the speed of the object during the time interval t = 2.0 seconds to t = 4.0 seconds?

parallel

The speed-time graph for a particle moving at constant speed is a straight-line ______________ to the time axis.

inertia

The tendency of a moving object to continue in a straight line or a stationary object to remain in place is called -

inertia

The tendency of matter to remain in constant motion unless acted on by an outside, unbalanced force is called

55 N south

Two people are pulling a refrigerator into a garage. One person is pulling south with 30 N of force, while the other person is pulling south with 25 N of force. What is the net force?

50 W

Using 1000. J of work, a small object is lifted from the ground floor to the third floor of a tall building in 20.0 seconds. What power was required in this task?

255 m

Verify the ranges for the projectiles motion for an initial velocity of 50 m/s at the given initial angles= 45 degree. ( g = 9.8 m/s^2)

30.6m

Water towers store water above the level of consumers for times of heavy use, eliminating the need for high-speed pumps. How high above a user must the water(densityl000kg/m3) level be to create a gauge pressure of 3.00 x 10^5N/m^2

the downward force exerted on an object due to gravity

Weight is best described as

buoyant force

What force makes you feel lighter in the water?

136 N

What force must be exerted on the master cylinder of a hydraulic lift to support the weight of a 2000-kg car (a large car) resting on the slave cylinder? The master cylinder has a 2.00-cm diameter and the slave has a 24.0-cm diameter.

0

What is the acceleration of a car that maintains a constant velocity of 55 mi/hr for 10.0 seconds?

$2.37

What is the cost of operating a 3.00-W electric clock for a year if the cost of electricity is $0.0900 per KW.h?

force divided by area

What is the formula for calculating pressure?

mass divided by volume

What is the formula for density?

a parabola

What is the path of a projectile (in the absence of friction)?

3rd

When a teacher stands at the front of the class, the force of gravity pulls her toward the ground. The ground pushes back with an equal and opposite force. This is an example of which of Newton's Laws of Motion?

45 degrees

Which angle produces the greatest range?

bathtub of cool water

Which has more internal energy, a bathtub full of cool water or a cup of hot water?

Newton's first law

Which law states the need to wear seatbelts?

Newton's first law

Which of Newton's Three Law does the following example illustrate? The blood in your head rushes to your feet when riding on an elevator this is descending and abruptly stops.

Newton's First Law

Which of Newton's Three Laws does the following statement satisfy? An object at rest tends to stay at rest and an object in motion tends to stay in motion in a straight line at a steady speed until an unbalanced force acts upon it.

Newton's Second Law

Which of Newton's Three Laws does the following statement satisfy? The relationship between an object's mass (m), its acceleration (a), and the applied force F is F=ma. Acceleration and force are vectors. This law requires that the direction of the acceleration vector is in the same direction as the force vector.

Newton's Second Law

Which of Newton's three laws does the following example illustrate? If you have a hockey puck sliding along a table, it will eventually come to a stop.

expansion

Which of the below is not a type of heat transfer?

The buoyant force of an object is equal to the weight of the fluid displaced by an object.

Which of the following is Archimedes' principle?

Fahrenheit

Which of the following is NOT a unit of heat?

force

Which of the following is defined as a push or a pull?

newton- meter per second

Which of the following is not a unit for power?

computer

Which of the following is not an exampie of a hydraulic system?

A car is moving with a high speed in straight line

Which one of the following is NOT consistent with a car which is accelerating?

20 m/s

Which one of the following quantities is NOT a vector?

30 and 60

Which two angles will produce the same range? (in degrees)

vector

Which type of quantity is characterized by both magnitude and direction?

it would sink

lf an object has a density of 14g/cm3 and it is put in a container of water, what would happen to it?