Question

1. Ball thrown at 45° with intial velocity of 25m/s.

Find the

A. Initial velocity

B. Final velocity

C. Acceleration (m/s²)

D. Time ( s )

E. Distance ( m )

Answer 1

Given:

$v_0=25\:\rm m/s$

$\theta=45^\circ$

(a)

$$v_{ix}=v_0\cos\theta=25\cos45^\circ=17.7\:{\rm m/s}\\ v_{iy}=v_0\sin\theta=25\sin45^\circ=17.7\:{\rm m/s}$$

(b)

$$v_{fx}=v_0\cos\theta=25\cos45^\circ=17.7\:{\rm m/s}\\ v_{fy}=-v_0\sin\theta=-25\sin45^\circ=-17.7\:{\rm m/s}$$

(c)

$$a_{x}=0\:{\rm m/s^2}\\ a_{y}=-g=-9.8\:{\rm m/s^2}$$

(d)

$$t=\frac{2v_0\sin\theta}{g}=\frac{2*25*\sin45^\circ}{9.8}=3.6\:\rm s$$

(e)

$$d=\frac{v_0^2\sin2\theta}{g}=\frac{25^2*\sin90^\circ}{9.8}=63.8\:\rm m$$