PHYSICS

Remains a non zero constant

For general projectile motion with no air resistance, the vertical component of a projectile's acceleration

false

If the velocity of an object is zero then that object cannot be accelerating

False

If three vectors add to zero, they must all have equal magnitudes.

they hit at the same time

In an air free chamber, a pebble is thrown horizontally and at the same instant a second pebble is dropped from the same height. compare the times of fall of the two pebbles

They hit at the same time

In an air-free chamber, a pebble is thrown horizontally, and at the same instant a second pebble is dropped from the same height. Compare the times of fall of the two pebbles

exactly g

suppose a ball is thrown straight up and experiences no appreciable air resistance

h

A 10-kg rock and a 20-kg rock are thrown upward with the same initial speed v0 and experience no significant air resistance. if the 10-kg rock reaches a maximum height h, what maximum height will the 20-kg ball reach?

The acceleration is downward during the entire time the ball is in the air

A ball is thrown directly upward and experiences no air resistance. Which one of the following statements about its motion is correct?

The ball

A ball is thrown horizontally from the top of a tower at the same instant that a stone is dropped vertically. Which object is traveling faster when it hits the level ground below if neither of them experiences any air resistance?

True

A boulder rolls off a very high cliff and experiences no significant air resistance. While it is falling, its trajectory is never truly vertical

Be directly over the package

A pilot drops a package from a plane flying horizontally at a constant speed. Neglecting air resistance, when the package hits the ground the horizontal location of the plane will

either the ball's velocity nor its acceleration are 0

A player kicks a soccer ball in a high arc toward the opponent's goal. At the highest point in its trajectory

Its horizontal velocity component is the same as it was just as it was launched.

A rock is thrown from the upper edge of a tall cliff at some angle above the horizontal. It reaches its highest point and starts falling down. Which of the following statements about the rock's motion are true just before it hits the ground? (There could be more than one correct choice.)

Is always zero

For general projectile motion with no air resistance, the horizontal component of a projectile's acceleration

Remains a non zero constant

For general projectile motion with no air resistance, the horizontal component of a projectile's velocity

James and John will reach the surface of the lake at the same time.

James and John dive from an overhang into the lake below. James simply drops straight down from the edge. John takes a running start and jumps with an initial horizontal velocity of 25 m/s. Compare the time it takes each to reach the lake below if there is no air resistance.

False

The magnitude of the resultant of two vectors cannot be less than the magnitude of either of those two vectors.

Increases

Two objects are dropped from a bridge, an interval of 1.0 s apart, and experience no appreciable air resistance. As time progresses, the DIFFERENCE in their speeds

they travel at same speed

What are their speeds when they HIT the street? Two objects are thrown from the top of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed.

The horizontal acceleration is always zero and the vertical acceleration is always a non-zero constant downward

Which of the following statements are true about an object in two-dimensional projectile motion with no air resistance? (There could be more than one correct choice)

The horizontal acceleration is always zero and the vertical acceleration is always a non-zero constant downward.

Which of the following statements are true about an object in two-dimensional projectile motion with no air resistance? (There could be more than one correct choice.)

false

if the acceleration of object is zero then its not moving

zero

when a ball is thrown straight