Question

A car moving with a velocity of 10 m/s change its velocity to 20 m/s. Acceleration of car is 4 m/s. After 5 sec car come to rest. Find the distance travelled in 5 sec

Answer 1

Answer:

37.5

Explanation:

acceleration = v-u

                          t

$4= \frac{20-10}{t}\\4= \frac{10}{t}\\transposing \\4t= 10\\t= \frac{10}{4}\\t= 2.5$

lets find the distance travelled in 2.5s

$s= ut+\frac{1}{2}at^2$

$s= 10\times 2.5 +\frac{1}{2}\times 4 \times 2.5^2\\s= 10\times 2.5+\frac{1}{2}\times 4 \times 6.25\\s= 25+\frac{1}{2}\times 25\\s= 25+12.5\\s= 37.5$

as the rest 5 seconds is rest there is no motion or distance covered to the final answer is 37.5 m in 5 seconds