Basic Motion
Which of the following is not a scalar quantity: speed, distance, velocity, or time?
Velocity
What condition must be met for an object to be in freefall?
Only gravity acts on the object.
What force opposes motion between sliding surfaces?
Friction Force
True of false: Something can accelerate without a net force present.
False
What is a summary of Newton's Third Law?
For every action there is an equal and opposite reaction (or something similar)
If Tyreek Hill runs 40 meters in 4.3 seconds, what is his speed?
9.3 m/s
A projectile has acceleration in what direction and with what magnitude?
9.8 m/s^2 downward
Which object has more inertia: a pencil or an airplane?
Airplane
If you double the net force and double the mass, what happens to acceleration?
Stays the same
If Lebron James' weight is 1000 N, by how much does he pull on the Earth?
1000 N
Define a scalar quantity.
A quantity that is solely defined by its magnitude.
If Jalen Hurts throws a football at a 20 degree angle and it goes 30 yards, at what angle would he need to throw the football for it to go the same distance (assuming he applies the same force and the football has no lift)?
70 degrees
If a car weighs 40,000 N, what is the normal force when it is sitting on a flat driveway?
40,000 N
What is the weight of a 100 kg Christmas tree?
980 N
If the Earth pulls on the golf ball, what is the reaction force?
The golf ball pulls on the Earth.
True of false: Acceleration can be negative.
True
If Jose Altuve drops a ball from the top of Minute Maid Park and it takes 4 seconds to hit the ground, what is the ball's final velocity? (Assume air resistance is negligible.)
39.2 m/s
If Mr. Milton and Mrs. Nquyen push a table to the right with 1000 N and Mr. Eshleman and Mr. Cruz push the table to the left with 1000 N, what is the net force?
If Bob Jr. pushes a 5 kg cart with 10 N to the left and Bob Sr. pushes with 20 N to the right, what is the magnitude and direction of the acceleration?
2 m/s^2 to the right
What caused the bottle rocket to go up in the demonstration last week.
Water pushed down by air pressure pushed back up.
Slope on a velocity-time graph determines what?
Acceleration
For an object in circular motion (like the moon around the Earth), what direction do the velocity and acceleration vectors point?
Velocity: Along the path (tangent)
Acceleration: Toward the center of the circle (centripetal)
True of false: The normal force always pushes up
False
What is the net force on a 2000 kg car moving at 30 m/s in a straight line?
0 N
In our lab from last week, name one interaction pair.
Cart pushing on ramp and the normal force on cart; Tension on cart/weight and tension string; Earth's gravity pulling on cart (or weight) and the cart's (or weight's) gravity pulling on the Earth.