Conceptual physics unit 1

what is the acceleration of a car that maintains a constant velocity of 100km/h for 10s

0m/s*2

The gain in speed each second for a freely falling object is about

10 m/s

A 1kg mass at the Earth's surface weighs

10N

The force of friction on a sliding object is 10n The applied force needed to maintain a constant velocity is

10n

a car starts from rest and accelerates at 6 m/s*2 How far does it travel in 3 seconds

27m

the average speed of a horse that gallops a distance of 100m in a time of 30 seconds is

3.3 m/s

an astronaut stands by the rim of a crater on the moon, where the acceleration of gravity is 1.62m/s*2. To determine the depth of the crater she drops a rock and measures the time it takes for it to hit the bottom. If the time is 6.3s what is the depth of the crater?

32m

A man weighing 800 N stands at rest on two bathroom scales so that his weight is distributed evenly over both scales. The reading on each scale is

400n

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

5n

When the velocity and acceleration of an object have opposite signs, the speed of the object increases

False

Newton's Third Law

For every action there is an equal and opposite reaction

The scientist to first introduce the concept of Inertia was

Galileo

If your automobile runs out of fuel while you are driving, the engine stops but you do not come to an abrupt stop. The concept that most explains why is

Inertia

A stone is thrown straight up. When it reaches its highest point

Its velocity is zero and its acceleration is not zero

Newton's Second Law

Net force and acceleration are proportional however acceleration is inverse to mass

Suppose that an object travels from one point in space to another. Make a comparison between the displacement and the distance traveled.

The displacement is ethier less than or equal to the distance traveled

Free fall is the motion of an object subject only to the influence of gravity

True

When the velocity and acceleration of an object have the same sign, the speed of the object increases

True

it is possible to have a zero acceleration and still be moving

True

When you stand at rest on a pair of bathroom scales, the readings on the scales will always

add to equal your weight

According to Newtons law of inertia, a rail road train in motion should continue going forever even if it's engine is turned off we never observe this because railroad trains

always have forces that oppose their motion

An object in mechanical equilibrium is an object

at rest moving with constant velocity having no acceleration

If no external forces are acting on a moving object, it will

continue moving at the same velocity

The two measurements necessary for calculating average speed are

distance/time

Whereas Aristotle relied on logic in explaining nature, Galileo relied on

experiment

Whirl a rock at the end of a string and it follows a circular path. If the string breaks, the tendency of the rock is to

follow a straight line path

One object has twice as much mass as another object. The first object also has twice as much

inertia

Whenever the net force on an object is zero, its acceleration

is zero

A kilogram is a measure of an object's

mass

When a rocket ship accelerating in outer space runs out of fuel it

no longer accelerates

Your weight is

the gravitational attraction between you and the earth

As an object freely falls, its

velocity increases