Kinemetics
Motion of an object thrown into the air, subject only to the force of gravity and air resistance (if present).
Projectile motion
A ball is thrown straight up into the air and comes back down to the same height. If it takes 4 seconds to reach the highest point, how long will it take to return to the thrower’s hand?
8 seconds.
What happens to the vertical velocity of a projectile at its highest point?
It becomes zero
A ball is thrown upward at 20 m/s. Ignoring air resistance, what will be its speed just before it returns back to the thrower’s hand?
20 m/s downward.
Which motion has constant velocity in projectiles?
Horizontal motion is uniform (constant velocity)
A skateboarder going down a hill speeds up. What causes the increase in speed?
Acceleration due to gravity pulling down the slope
Which motion in a projectile is affected by the acceleration due to gravity of Earth?
Vertical Motion
When a person jumps off a diving board and follows a curved path into the water, what type of motion is this?
Projectile motion
What is the standard value of acceleration due to gravity on Earth?
9.8m/s2 downward
A student throws a stone straight upward with an initial velocity of 12 m/s.
How high will the stone travel before it starts coming back down?
h = v^2 / 2g
h=7.35m