Question

8. Given that the total distance travelled is 1.4 km, and the

acceleration is 4 m/s² for the first T seconds, find:
a) the value of V
b) the value of T.

Answer 1

Explanation:

Formula for distance travelled:

x= ut + 1/2at^2

x is 1.4km, convert this to m since acceleration is in m, = 1400m

u is initial velocity, in this case assume 0

a is acceleration, = 4m/s^2

t is unkown and what we want to find out

Substitute value into formula,

1400 = 0t + 1/2(4)t^2

1400 = 2t^2

t^2 = 1400/2

t^2 = 700

t = 26.458s

Formula for acceleration:

a = (v-u)/t

at= v-u

Substitute value,

4(26.458) = v - 0

v = 105.832 m/s