Answer: (A) acceleration = -3.6m/s². This is deceleration or negative acceleration.
(B) Therefore, velocity just before impact, v = 8.4m/s
Explanation:
(a) Initial velocity, u = 56km/h = (56*1000/3600)m/s = 15.6m/s
Distance, s = 24.0m, time, t = 2.0s, acceleration, a = ?
<em>Using the equation, s = ut + 1/2at</em>²
24.0m = 15.6m/s * 2s + (a * 2²)/2
24.0 = 31.2 +2a
2a = -31.2 + 24
2a = -7.2
a = -7.2/2
acceleration = -3.6m/s². This is deceleration or negative acceleration.
(b) final velocity just before impact, v = ? initial velocity, u = 15.6m/s, acceleration = -3.6m/s², time, t = 2.0s
using the equation <em>v = u + at</em>
v = 15.6m/s + (-3.6m/s² * 2s)
v = 15.6m/s - 7.2m/s
v = 8.4m/s
Therefore, velocity just before impact, v = 8.4m/s
