The 10 kg dancer leaps into the air with an initial velocity of 5 m/s at angle of 45° from the floor. How far will she travel in the air horizontally before she lands on the ground again?

2.55 m

Explanation:

The motion of the dancer is the motion of a projectile, which consists of 2 independent motions:

- A uniform motion (constant velocity) along the horizontal direction

- A uniformly accelerated motion (constant acceleration) along the vertical direction

The horizontal range of a projectile can be found by using the equations of motions along the two directions, and it is given by:

where

v is the intial velocity

is the angle of projection

is the acceleration due to gravity

For the dancer in this problem, we have:

v = 5 m/s

Therefore, the horizontal range is:

none, its a machine

the answer is b i think