64 terms

Claims that appear to be pseudoscience should be?

tested experimentally

The re-creation of an event by comparing two situations in which all the factors are identical except one is called a?

controlled experiment

A tentative scientific explanation which may or may not be rejected upon further experimentation is called a?

hypothesis

An object accelerates when it slows or its direction of movement changes. (True or False)

True

In the equation v=d/t, v represents

average speed

A car traveling at 20 mph on a curved exit ramp has

constant speed and variable velocity

60 mph would convert to?

26.8 m/s

If you double the mass of an object while an unbalanced force remains constant?

the acceleration of the object is halved

Ignoring air resistance, the velocity of a falling object?

is constantly increasing

When you roll a ball across the floor, it comes to a stop because you are no longer exerting a force on it? (True or false)

false

The weight of a 50-kg box is closest to?

500 N

The tendency of a moving object to remain in unchanging motion in the absence of an unbalanced force is called?

inertia

A 1-kg ball is thrown at 10 m/s straight upward. Neglecting air resistance, the net force that acts on the stone when it is halfway to the top of its path is about?

10 N

A 10-N falling object encounters 4 N of air resistance. The net force on the object is?

6 N

A 2000-kg car experiences a braking force of 10,000 N and skids to a stop in 6 seconds. The speed of the car just before the brakes were applied was?

30 m/s

A 1000-kg automobile enters a freeway on-ramp at 20 m/s and accelerates uniformly up to 40 m/s in a time of 10 seconds. How far does the automobile travel during that time?

300 M

A baseball player bats a ball with a force of 1000 N. The reaction force that the ball exerts against the bat is?

1000 N

A car accelerates at 2 meters/s/s. Assuming the car starts from rest, how far will it travel in 10 s?

100 m

An object falls freely from rest on a planet where the acceleration due to gravity is twice as much as it is on Earth. In the first 5 seconds it falls a distance of?

250 m

Arnold Strongman and Suzie Small each pull very hard on opposite ends of a massless rope in a tug-of-war. The greater force on the rope is exerted by?

both the same

A 10-kg brick and a 1-kg book are dropped in a vacuum. The force of gravity on the 10-kg brick is?

10 times as much force as the force on the 1-kg book

A ball is thrown upwards and returns to the same position. Compared with its original speed after release, its speed when it returns is about?

the same

A block is dragged without acceleration in a straight-line path across a level surface by a force of 6 N. What is the force of friction between the block and the surface?

6 N

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?

zero

A horse gallops a distance of 10 kilometers in a time of 30 minutes. Its average speed is?

20 km/hr

A large and a small person wish to parachute at equal terminal velocities. The larger person will have to?

get a larger parachute

A rock weighs 30 N on Earth. A second rock weighs 30 N on the moon. Which of the two rocks has the greater mass?

the one on the moon

If less horizontal force is applied to a sliding object than is needed to maintain a constant velocity?

the object eventually slides to a stop

You should "follow through" when hitting a ball because?

of the relationship between Δp = F Δt

Suppose you slowly, and at constant speed, lift a book weighing 12 N from the floor to a shelf 2 m above the floor. Neglect air resistance. While you are lifting, the net force on the book is?

zero

A 10-N block and a 1-N block lie on a horizontal frictionless table. To provide them with equal horizontal acceleration, we would have to push with?

10 times as much force on the heavier block

A automobile and a baby carriage traveling at the same speed collide head-on. The impact force is?

the same for both

A player catches a ball. Consider the action force to be the impact of the ball against the player's glove. The reaction to this force is the?

force the glove exerts on the ball

An object is pulled northward by a force of 10 N and at the same time another force of 15 N pulls it southward. The magnitude of the resultant force on the object is?

5 N

The human body can, under certain conditions, withstand an acceleration of 10 g. What net force would produce this acceleration of a 50-kg person?

5000 N

Two billiards balls, each of mass m, move towards each other at same speeds, v and collide head on. Their combined momentum after the collision is?

0

"Energy" could best be defined as?

the capacity to do work

A 2000 N car travels 50 m along a level road, powered by a drive force of 1000 N. The work done by the drive force is?

50,000 J

In its monthly bill, the electric company charges you primarily for?

the electric energy you consume every month

If work was done on an object, the object must have?

changed its position

How much work do you do when you lift a 3 N apple by 2 m during a time of 6 s?

6 J

In order for you to get out of bed with the least amount of work, would it be better for your bed to be on the floor or a meter high?

It would be better for the bed to be a meter high, because then you would not need to do as much work in lifting yourself to your feet.

n order to quadruple an object's kinetic energy, we must?

double its speed

Nearly all of the energy consumed today is provided by petroleum, coal, hydropower and nuclear sources. (true or false)

true

One joule is the same as one

one newton-meter

he energy transformation that occurs during downhill skiing is?

grav E leads to kin E + therm E.

Two students stand poised to leap off a high dive structure into the swimming pool below. Student B is twice as massive as student A. Which of the following is true?

student B did twice as much work climbing to the top of the structure

Which of the following energy transformations represents the operation of a wind turbine [a device that uses the wind as an energy resource]?

Kin E leads to Electric E

basic SI unit for mass

Kilogram

basic SI unit for distance

meter

basic SI unit for time

second

Average Speed

your total distance traveled divided by the total time traveling

Instantaneous Speed

your speed at a given instance

Velocity

speed and direction

Difference between speed and velocity

relates to vectors and arrows.

same lengths=same speeds

different directions=different velocities

same lengths=same speeds

different directions=different velocities

Acceleration

change in velocity divided by the time taken

Newton's first law of motion

If no external forces act on a moving object, then its

motion will continue on without changing.

motion will continue on without changing.

Newton's second law of motion

If a force F is applied to an object of mass m, the

object experiences a nonzero acceleration a in the

direction of the applied

object experiences a nonzero acceleration a in the

direction of the applied

Why do things accelerate?

Objects will continue to move in the same direction and at a constant speed unless a force is applied

mass

amount of matter in an object

weight

is the force gravity exerts on a body

Newton's third law of motion

For every applied force, there also occurs a force of equal magnitude acting in the opposite direction at precisely the same point.

Action force (example)

you pushing on a wall with your hand

reaction force (example)

the wall pushes back on your hand with an equal and opposite force