# help with physics pleasee?

The acceleration due to gravity on the moon is 1.6m/s^2(down). if a baseball was thrown with an initial velocity of 4.5m/s(up). what would its velocity be after 4.0s??

### 4 Answers

- Jim MoorLv 72 months agoBest Answer
v = gt + v₀

v = (-1.6m/s²) (4.0s) + 4.5m/s

note: gravity is negative for down, initial velocity is positive for up.

v = -6.4 + 4.5

v = -1.9 m/s so in a downward direction

note: 2 decimal places (always check sigfigs last)

- MyRankLv 62 months ago
Given,

Acceleration due to gravity (g) = -1.6m/sec²Initial velocity (u) = 4.5m/secFinal velocity (v) = ?Time (t) = 4secUsing kinematic relation:-v = u + gt= 4.5m/sec + (-1.6m/sec²) x 4sec= 4.5 m/sec - 6.4m/sec = -1.9 m/sec∴ final velocity (v) = -1.9m/sec.

Source(s): http://myrank.co.in/ - electron1Lv 72 months ago
Use the following equation.

vf = vi + a * t

vf = 4.5 + -1.6 * 4 = -1.9 m/s

The negative sign means the baseball is moving down.