Conceptual Physics Speed Quiz 1

B. in equilibrium.

A hockey puck sliding at constant velocity across the ice is A. nearly in equilibrium. B. in equilibrium. C. is nowhere near being in equilibrium. D. none of the above

B. not vertical.

A pair of wires support a heavy painting. Tension in the wires is greater when they are A. vertical. B. not vertical. C. the same regardless of the wire orientation. D. none of the above

A. keep rolling if friction is absent.

Galileo taught us that if you roll a ball along a level surface it will A. keep rolling if friction is absent. B. soon roll in the opposite direction. C. roll as long as its inertia nudges it along. D. soon slow down due to its natural place.

B. zero.

The net force on any object in equilibrium is A. equal to its weight. B. zero. C. non-zero when motion is involved. D. less than its weight.

B. in the absence of a retarding force, a body will keep moving at a constant speed in a straight line forever

What did Galileo discover about moving bodies and force in his experiments with inclined planes? A. Bodies rolling down a steep inclined plane starting at a given height rolled up a gently inclined plane to a higher height. B. In the absence of a retarding force, a body will keep moving at a constant speed in a straight line forever. C. Bodies rolling up an inclined plane sped up. D. Bodies rolling down an inclined plane slowed down.

B. Galileo found that a heavier stone does not fall significantly faster than a lighter one

What did Galileo discover in his legendary experiment on the Leaning Tower of Pisa? A. Galileo found that a heavier stone falls significantly faster than a lighter one. B. Galileo found that a heavier stone does not fall significantly faster than a lighter one. C. Galileo found that air resistance significantly slowed falling stones. D. Galileo found that stones fall faster proportional to their weight.

C. an object in mechanical equilibrium experiences a zero net force

What does it mean to say something is in mechanical equilibrium? A. An object in mechanical equilibrium experiences a net force twice its weight. B. An object in mechanical equilibrium must experience no forces. C. An object in mechanical equilibrium experiences a zero net force. D. An object in mechanical equilibrium is always in motion.

A. Inertia is the tendency of a body to maintain its state of motion in the absence of applied forces

What is inertia? A. Inertia is the tendency of a body to maintain its state of motion in the absence of applied forces. B. Inertia explains why things stay at rest but not why they stay in motion. C. Inertia describes why it is easier to get a massive ball moving than it is to get a less massive one moving. D. Inertia explains why things stay in motion but not why they stay at rest.

D. 5 N to the right

What is the net force acting on the box?

D. the net force is zero newtons

What is the net force on a bag pulled down by gravity with a force of 18 newtons and pulled upward by a rope with a force of 18 newtons? A. The net force is 18 newtons. B. The net force is 36 newtons. C. The net force is 25 newtons. D. The net force is zero newtons.

D. none of the above

Which of the following is a vector quantity? A. mass B. area C. volume D. none of the above

A. Yes, the bowling ball is in equilibrium because ΣF = 0.

A bowling ball at rest is in equilibrium. Is the ball in equilibrium when it moves at constant speed in a straight-line path? A. Yes, the bowling ball is in equilibrium because ΣF = 0. B. The bowling ball is not in equilibrium because ΣF = -mg. C. The bowling ball is not in equilibrium because the wood of the bowling alley exerts an upward force on the ball. D. The bowling ball is not in equilibrium because it is moving.

C. both of the above

A bowling ball is in equilibrium when it A. is at rest B. moves steadily in a straight-line path C. both of the above D. none of the above

A. 5 N to the left

A cart is pulled to the right with a force of 15 N while being pulled to the left with a force of 20 N. The net force on the cart is A. 5 N to the left B. 5 N to the right C. 25 N to the left D. 25 N to the right

D. none of the above

A hockey puck is set in motion across a frozen pond. If ice friction and air resistance are neglected, the force required to keep the puck sliding at constant velocity is A. equal to its weight. B. equal to its weight divided by its mass. C. equal to its mass times its weight. D. none of the above

C. of friction.

A hockey puck sliding across the ice finally comes to rest because A. that's just the way it is. B. it seeks its proper and natural state. C. of friction.

A. the diagonal is the resultant, or sum, of two vectors

According to the parallelogram rule, what quantity is represented by the diagonal of a constructed parallelogram? A. The diagonal is the resultant, or sum, of two vectors. B. The diagonal is always 1.41 times the magnitude of the sum of the vectors. C. The diagonal is the difference of two vectors. D. The diagonal is 1.41 times the magnitude of the longest vector.

D. 400 N

Burl and Paul have a total weight of 1300 N. The tensions in the supporting ropes that support their scaffold add to 1700 N. The weight of the scaffold itself must be A. 600 N. B. 500 N. C. 300 N. D. 400 N

A. the tension in each rope would be half of the gravity force

Consider Nellie hanging at rest in Figure 2.11. If the ropes were vertical, with no angle involved, what would be the tension in each rope? A. The tension in each rope would be half of the gravity force. B. The tension would be zero in both ropes. C. The tension in each rope would be twice the gravity force. D. The tension in each rope would be equal to the gravity force.

D. slow down the ball's changes in speed.

Galileo's use of inclined planes allowed him to effectively A. eliminate all changes in speed. B. reduce the time of the ball's changes in speed. C. eliminate friction. D. slow down the ball's changes in speed.

D. Newton refined Galileo's concept of inertia and made it his first law of motion

How does Newton's first law of motion relate to Galileo's concept of inertia?A. Newton replaced Galileo's concept of inertia with his three laws of motion. B. Newton's first law of motion refuted Galileo's concept of inertia. C. Newton expressed Galileo's concept of inertia with the inertia equation. D. Newton refined Galileo's concept of inertia and made it his first law of motion.

D. The frictional force on the crate is 100 N opposite the direction of motion.

If you push on a crate with a horizontal force of 100 N and it slides at constant velocity, what is the magnitude and direction of the frictional force acting on the crate? A. The frictional force on the crate is 100 N in the same direction as the direction of motion. B. The frictional force has nothing to do with you pushing on the crate. C. The frictional force on the crate is zero newtons. D. The frictional force on the crate is 100 N opposite the direction of motion.

C. inertia.

If your automobile runs out of fuel while driving, the engine stops. You don't come to an abrupt stop due to A. the principle of continuation. B. resistance. C. inertia. D. gravity.

D. All of the above are correct

Referring to the figure, which of the following are true statements? A. 50 N is the resultant of the 30- and the 40-N vectors. B. The 30-N vector can be considered a component of the 50-N vector. C. The 40-N vector can be consided a component of the 50-N vector. D. all of the above are correct

A. vector quantities

The equilibrium rule, EF=0, applies to A. vector quantities B. scalar quantities C. both of the above D. none of the above

A. 10 N.

The force of friction on a sliding object is 10 N. The applied force needed to maintain a constant velocity is A. 10 N. B. more than 10 N. C. less than 10 N.

B. the net force is 70 pounds to the right

What is the net force on a cart that is pulled to the right with 100 pounds of force and to the left with 30 pounds of force? A. The net force is zero. B. The net force is 70 pounds to the right. C. The net force is 70 pounds to the left. D. The net force is 130 pounds.

D. The net force is zero.

What is the net force on an object in either static or dynamic equilibrium? A. The net force is vertical for static equilibrium and horizontal for dynamic equilibrium. B. The net force is equal and opposite to the weight of the object. C. The net force is zero for static equilibrium and greater than zero for dynamic equilibrium. D. The net force is zero.

B. it continues to move in a straight line a constant speed

What type of path does a moving object follow in the absence of a force? A. It follows a circular path in the absence of a force. B. It continues to move in a straight line at a constant speed. C. It moves in a straight line and eventually slows to a stop. D. It follows a parabolic trajectory in the absence of a force.

C. he discovered that a ball rolling down an incline and onto a horizontal surface would roll indefinitely

What was the greatest discovery by Galileo during his inclined-plane experiments? A.He discovered that heavy objects roll faster than light objects on an incline. B. He discovered that balls rolling down an incline gain speed and balls rolling up an incline lose speed. C.He discovered that a ball rolling down an incline and onto a horizontal surface would roll indefinitely. D. He discovered that light and heavy objects gain the same speed when rolling on inclines.

A. half her weight

When Nellie Newton hangs by the ends of a rope draped over a large pulley, the tension in each supporting vertical strand is A. half her weight. B. equal to her weight. C. twice her weight. D. none of the above

D. Any of the above depending on the directions of forces.

When a pair of 10-N forces act on a box of candy, the net force on the box is A. about 14 N. B. 20 N. C. zero. D. Any of the above depending on the directions of forces.

B. back of the cart hits the ball.

When you quickly jerk a cart forward that has a ball resting in the middle, the A. neither, for the ball rides along in the middle as the cart moves forward. B. back of the cart hits the ball. C. front of the cart hits the ball. D. All of the above depending on how quickly the cart is pulled.

C. your weight is equal in magnitude and opposite in direction to the support force from the scale

When you stand at rest on a bathroom scale, how does your weight compare with the support force from the scale? A. Your weight is equal in magnitude and in the same direction as the support force from the scale. B. The support force from the scale is twice your weight. C. Your weight is equal in magnitude and opposite in direction to the support force from the scale. D. The support force from the scale is half your weight.

B. half your weight

When you stand on two bathroom scales with one foot on each scale and with your weight evenly distributed, each scale will read A. your weight B. half your weight C. zero D. more than your weight

C. your tendency to keep moving forward.

While you are standing in the aisle of a bus, the driver suddenly makes a left turn. You lurch to the right due to A. an equilibrium challenge. B. an unbalanced force. C. your tendency to keep moving forward.

C. in your hand

You are riding in a vehicle at a steady speed and toss a coin straight upward. Where will the coin land? A. behind you B. ahead of you C. in your hand D. there is not enough information

C. equal to 75 N

You push a crate at a steady speed in a straight line. If the friction force is 75 N, how much force must you apply? A. more than 75 N B. less than 75 N C. equal to 75 N D. not enough information