Projectile Motion Vocab and Assumptions

Match the following variables with their units

• s

• Time

• m

• Distance

• N

• Force

• m/s

• Velocity

• m/s^2

• Acceleration

Match the following variables with their units

• m/s

• Displacement

• m

• acceleration due to gravity

• kg

• Torque

• Nm

• mass

• m/s^2

• vi

What assumption can you make for the acceleration, in the x-component of projectile motion?

• -9.8 m/s^2

• 0 m/s^2

Answer explanation

The assumption for the acceleration in the x-component of projectile motion is 0 m/s^2, as there is no acceleration in the horizontal direction.

What assumption can you make for the acceleration, in the y-component of projectile motion?

• -9.8 m/s^2

• 0 m/s^2

Answer explanation

The assumption for the acceleration in the y-component of projectile motion is -9.8 m/s^2, which is the acceleration due to gravity.

What assumption can you make for the initial velocity, in the y-component of projectile motion?

• Initial velocity is greater in the y-direction

• No initial velocity in the y-direction

• Initial velocity is the same in both x and y directions

Answer explanation

The assumption for the initial velocity in the y-component of projectile motion is that there is no initial velocity in the y-direction.

What assumption can you make for time in projectile motion?
T_x​ ​ (a)   T_y​

• >

• <

• =

Answer explanation

The assumption for time in projectile motion is that the horizontal and vertical components of motion are independent.

What equation would you use if you are missing the variable v_f? (You're not trying to solve for v_f)

Answer explanation

The equation missing the variable v_f is Δx = (v_it) + (.5at²). This equation represents the displacement of an object with initial velocity v_i, constant acceleration a, and time t.

What equation would you use if you are missing the variable v_i? (You're not trying to solve for v_i)

Answer explanation

The equation missing the variable v_i is Δx = (v_ft) - (.5at²). This equation represents the displacement with initial velocity, final velocity, acceleration, and time.

Answer explanation

The equation missing the variable Δx is a=(v_f-v_i)/t. This equation represents the acceleration of an object given its final velocity (v_f), initial velocity (v_i), and time (t).

What equation would you use if you are missing the variable a? (You're not trying to solve for a)

Answer explanation

The equation missing the variable a is Δx=.5(vi+vf)t