Question

a projectile is thrown from the top of a 97 m tall building with an initial velocity of 13 m/s in the x direction. how fast will the projectile be moving just before it strikes the ground?

Answer 1

The speed of the projectile before it hits the ground is 45.5 m/s.

How to calculate the velocity of the projectile?

The speed of the projectile before it hits the ground is calculated by applying the following formula as shown below.

v = u + gt

where;

• v is the final velocity in y direction
• u is the initial velocity in y direction
• t is time of motion

The time of motion is calculated as;

t = √ (2h/g)

t = √ (2 x 97 / 9.8)

t = 4.45 s

The final vertical velocity;

v = 0 + 4.45 x 9.8

v = 43.61 m/s

The resultant final velocity is;

v = √(vx² + vy²)

v = √ (13² + 43.61²)

v = 45.5 m/s