Physical Science - Ch. 10 - Review

What is the speed of an object at rest? a. 0 km/h b. 1 km/h c. 15 km/h d. This cannot be determined without further information.

a. 0 km/h

Force is a quantity made up of a. magnitude and direction. b. time and acceleration. c. mass and velocity. d. weight and speed.

a. magnitude and direction

Net force is a. the force acting in the opposite direction of an object's movement. b. the combination of all forces acting on an object. c. the force of gravity pulling an object down. d. the force acting in the same direction as an object's movement.

b. the combination of all forces acting on an object

An example of constant acceleration is a. static friction. b. uniform circular motion. c. average speed. d. balanced forces.

b. uniform circular motion.

Which is NOT a way to reduce friction? a. Put ball bearings between wheels and axles. b. Use lubricants on engine parts. c. Set a paperweight on notebook paper. d. Make surfaces smoother.

c. Set a paperweight on notebook paper

Which of the following situations best demonstrates the effects of friction? a. two trucks colliding b. a loaded slingshot c. a parachutist descending to the ground d. an apple falling from a tree

c. a parachutist descending to the ground

Accelerating can mean a. slowing down. b. speeding up. c. all of these. d. changing direction.

c. all of these

Displacement a. is the change in position of an object b. must be in a straight line c. all of these d. must be in a particular direction

c. all of these

Which is an example of harmful friction? a. sand on icy roads b. all of these c. engine parts wearing out d. brakes stopping a car

c. engine parts wearing out

The friction between the air and the surface of a moving object is a. molecular friction. b. rolling friction. c. fluid friction. d. static friction.

c. fluid friction

The _______ of an object consists of its speed and direction. a. displacement b. average speed c. velocity d. instantaneous speed

c. velocity

An example of helpful friction is a. scraping your knee on the floor. b. getting holes in your socks. c. writing on paper with a pen. d. car tires wearing out.

c. writing on paper with a pen

Which of the following speeds is the most accurate? a. 100 miles per day b. 100 miles per minute c. 100 miles per hour d. 100 miles per second

d. 100 miles per second

On a bus traveling south at 15.0 m/s, a child walks south at 2.5 m/sec. What is the child's resultant velocity? a. 17.5 m/s south b. 12.5 m/s north c. 17.5 m/s north d. 12.5 m/s south

a. 17.5 m/s south

Which of the following is a displacement? a. 3 miles north b. -0.2 ft/sec² c. 3 miles d. 7 ft/sec

a. 3 miles north

Which straight-line acceleration indicates an increase in speed? a. 4 m/s² b. 0 m/s² c. -15 m/s² d. All of these

a. 4 m/s²

Which of the following statements is true? a. Frictional forces are greatest when both surfaces are rough. b. When a truck is parked on a hill, friction pulls the truck down the hill. c. Friction can exist between two objects even when they are not in contact. d. Air resistance always opposes friction.

a. Frictional forces are greatest when both surfaces are rough

Which is an example of balanced forces acting on an object? a. a leaf lying on the grass b. a kangaroo jumping c. a cyclist slowing down d. a car turning a corner

a. a leaf lying on the grass

Centripetal acceleration occurs because an object is a. changing direction. b. slowing down. c. speeding up. d. all of these.

a. changing direction

The difference between speed and velocity is that velocity includes a. direction. b. weight. c. distance. d. time.

a. direction

The friction between the bristle of your toothbrush and the surfaces of your teeth is an example of a. helpful friction b. all of these c. rolling friction d. static friction

a. helpful friction

When an object changes position relative to a reference point, the object is a. in motion. b. stationary. c. moving at a constant velocity. d. moving at a constant speed.

a. in motion

If the net force acting on a stationary object is zero, then the object will a. remain at rest. b. accelerate in the direction of the strongest force. c. begin moving backwards. d. decelerate at a steady rate of speed.

a. remain at rest

How can the friction on a water slide be reduced? a. run a constant stream of water down the slide b. keep the surface of the slide dry c. increase the slope of the slide d. warm the surface of the slide

a. run a constant stream of water down the slide

An object is in motion when a. the object changes position relative to a stationary reference point. b. the object's speed increases. c. the object's displacement is greater than the distance traveled. d. you observe the object move.

a. the object changes position relative to a stationary reference point

Which of the following does NOT indicate velocity? a. 80 km/h going from New York toward New Jersey b. 28 km from Los Angeles to Catalina Island c. 40 km/h toward the town square along the main street d. 14 m/s SSE

b. 28 km from Los Angeles to Catalina Island

What does it mean when a change in velocity is negative? a. The object is changing direction. b. The object is slowing down. c. The object is speeding up. d. The object is falling down.

b. The object is slowing down

An airplane is flying at 635 km per hour at an altitude of 35,000 m. It is currently over Kansas and is approximately 16 minutes ahead of its scheduled arrival time. What is its velocity? a. 635 km/h b. This cannot be determined without further information about its direction. c. 35,000 m/s d. 16 m/min

b. This cannot be determined without further information about its direction

Which of the following best illustrates balanced forces? a. a rock falling to the ground b. a stretched rubber band being held between two hands c. a crash between a large truck and a train d. a person lifting a heavy box off of the ground

b. a stretched rubber band being held between two hands

Without friction you could not a. clean a pan. b. all of these c. write a letter. d. ride a skateboard.

b. all of these

The distance traveled by an object divided by the time it takes to travel that distance is called a. average acceleration. b. average speed. c. average velocity. d. activity.

b. average speed

If the net force on an object is zero then the object has a. reaction forces. b. balanced forces. c. unbalanced forces. d. action forces

b. balanced forces

In order to determine speed, you must know a. distance b. both time and distance c. time. d. none of these

b. both time and distance

Displacement must always indicate a. time. b. direction. c. velocity. d. speed.

b. direction

Friction is defined as a. speed of an object in a particular direction. b. force that opposes motion between two surfaces that are touching. c. resistance of an object to a change in its velocity. d. rate at which velocity changes.

b. force that opposes motion between two surfaces that are touching

In order to increase a car's speed, the force pushing it forward must be a. equal to the force of friction. b. greater than the force of friction. c. rolling friction. d. a negative force.

b. greater than the force of friction

An object experiencing balanced forces a. is speeding up. b. has a net force of zero. c. is slowing down. d. stops moving.

b. has a net force of zero

The combination of all of the forces acting on an object is called the a. union of forces. b. net force. c. total force. d. super force.

b. net force

A force is continuously applied to an object, causing it to accelerate. After a period of time, however, the object stops accelerating. What conclusion can be drawn? a. Gravity on the object has increased. b. The mass of the object has increased. c. The object is experiencing some kind of friction. d. The momentum of the object has reached a maximum.

c. The object is experiencing some kind of friction

A car is parked on a hill. In order to keep the car from rolling downhill, how great must the static friction acting on the car be? a. greater than the force pulling the car downhill b. smaller than the force pulling the car uphill c. equal to the force pulling the car downhill d. greater than the force pulling the car uphill

c. equal to the force pulling the car downhill

Which is an example of static friction? a. driving a car up a hill b. pulling a skier behind a boat c. pushing a box that is at rest d. braking a car going down a hill

c. pushing a box that is at rest

Which is NOT an example of sliding friction? a. pushing a book across a table b. ice skating on a frozen pond c. rolling a ball across a desk d. taking notes with a pencil

c. rolling a ball across a desk

Which of these is constant during uniform circular motion? a. direction b. displacement c. speed d. velocity

c. speed

A tug-of-war that results in one team pulling the other across the line is an example of a. action forces. b. balanced forces. c. unbalanced forces. d. reaction forces.

c. unbalanced forces

When velocity changes by the same amount over each time interval, acceleration is a. positive b. negative c. zero d. constant

d. constant

Average speed can be represented by the mathematical expression a. time - distance b. time + distance c. time * distance d. distance / time

d. distance / time

When the velocity of an object changes, it is acted upon by a(n) a. deceleration. b. momentum. c. inertia. d. force.

d. force

Which is an example of kinetic friction? a. friction between a sticky note and the page of a book as it marks your place b. friction between your skin and a pencil as it rests in your palm c. friction between your shoes and the ground when you stand still d. friction between a car's windshield and the air as you drive into the wind

d. friction between a car's windshield and the air as you drive into the wind

The SI unit for acceleration is a. ft/s². b. ∆v/t. c. mph. d. m/s²

d. m/s²

Acceleration is defined as the change in velocity divided by a. final velocity. b. speed. c. distance. d. time.

d. time