Gravity
98 Newtons (about 100 Newtons).
What forces are acting on a ball sitting still on the ground?
The force of gravity and the normal force of the ground.
A curved line on a speed graph means that the speed is _______________.
Accelerating. (Changing)
What is the energy of motion?
Kinetic energy
The distance traveled over time is the definition of ___________.
Speed
If I drop an object, what will happen?
a. It will fall towards the Earth accelerating at 9.8 m/s2.
b. It will fall towards the Earth with a speed of 9.8 m/s.
a. It will fall towards the Earth accelerating at 9.8 m/s2.
F = m * a summarizes which of Newton's Laws?
The second law.
Acceleration is _______________.
a. Constant speed
b. Going slower
c. Going fast
d. Change in speed over time
d. Change in speed over time
Two rocks rolled down a hill. They both weigh the same. If they are rolling at the same speed, which one has more kinetic energy?
They both have the same kinetic energy.
The energy of position. The energy that you gave to a marble when you held it on the ruler ramp.
Potential energy
What is the acceleration of gravity on Earth in m/s2?
9.8 m/s2.
Use Newton's first law to explain why a ball moves when I kick it.
An object at rest (the ball) stays at rest until acted upon by an outside force (kicking it).
A car travels 30 kilometers (km) in 3 hours. What is its average speed?
10 km per hour
Person A is standing on a box that is 1 foot tall. Person B is standing on a box that is 3 feet tall. Which person has more potential energy.
Person B
A push or a pull.
Which is a unit of weight?
a. Kilograms
b. Newtons
c. Calories
b. Newtons
The law of inertia is also known as which of Newton's Laws?
Newton's first law.
Person B ran faster (1 m/s) than Person A (0.8 m/s).
What is the most impactful to the kinetic energy of an object?
a. The mass
b. The speed
c. The force
b. The speed
The force of attraction between two objects.
Gravity
The gravitational force on the moon is 0.166 g. Compare the weight of a 100-kg astronaut on Earth and on the moon.
The astronaut weighs less on the moon than Earth.
Which of Newton's Laws would be most helpful in playing pool?
The third law (for every action there is an equal and opposite reaction).
A car travels at 10 meters per second for 3 seconds, then slows down at a rate of 1 meter per second for 2 seconds. How fast was it traveling at 4 seconds?
9 m/s
The ball on Earth.
How much stuff an object has.
Mass