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Option 1: Just fill in the form with your homework question, and someone will respond shortly with an answer.

Option 2: Take a photo (or link) of your question, and email or text it to us.

## Horizontal Launch off a Cliff

Q: An object is launched horizontally off a cliff with a velocity of 14 m/s. a) How long will it be in the air for? b) How far, horizontally, will the ball move before hitting the ground?

A: The keys to this question is that horizontal velocity is constant, and initially the vertical velocity . . . → Read More: Horizontal Launch off a Cliff

## Ball thrown vertically upwards

Q: A tennis ball is thrown vertically upward with an initial velocity of +6.7 m/s. What will the ballâ€™s velocity be when it returns to its starting point? The acceleration of gravity is 9.81 m/s^2.

A:

Its velocity will be – 6.7 m/s.

This is true for anything that is thrown vertically upwards. Look . . . → Read More: Ball thrown vertically upwards

## Kinematics Equations

Q: What are the kinematics equations?

Where = displacement = initial velocity = final velocity = acceleration = time

These are very useful, and you will use them many times before you are finished Physics 11. It would definitely help to memorize . . . → Read More: Kinematics Equations

## Vertical Motion of a Rocket

Q: A rocket moves upward, starting from rest with an acceleration of 27.2 m/s2 for 3.49 s. It runs out of fuel at the end of the 3.49 s, but does not stop. How high does it rise above the ground?

A: Okay the rocket’s moving up with an acceleration of +27.2m/s^2 for a . . . → Read More: Vertical Motion of a Rocket

## Tips to Remember for Kinematics and Projectile Questions

Some things you should know for projectiles (note that you haven’t done anything with angles yet, so you can ignore the sine and cosine parts):

The vertical and horizontal components are independent of each other. The vertical velocity is usually Vy = V*sin(Ï´) horizontal velocity is usually Vx = V*cos(Ï´), where V is the . . . → Read More: Tips to Remember for Kinematics and Projectile Questions

## An arrow is shot off a cliff at an angle, with crosswind

Q: A student standing on the top of a cliff shoots an arrow from a height of 30.0 m at 25.0 m/s and an initial angle of 32.0Â° above the horizontal. There are four parts to this question.

a) What will be the horizontal and vertical components of the arrowâ€™s initial speed?

Horizontal component . . . → Read More: An arrow is shot off a cliff at an angle, with crosswind