A car is traveling at the posted speed limit of 6.70 m/s (15 miles/h) in a school zone. The car passing a school bus when a child darts out from in front of the bus. The car is 10.0 m from the child when the driver of the car applies the brakes. The car decelerates at a constant rate of 4.00 m/s2 until coming to a halt. Calculate the

(a) distance of the car travels while decelerating and

(b) distance required to stop if the car is initially traveling at 13.4 m/s (30.0 miles/h).

Question

Physics

Monserrat

19 March, 19:50

A car is traveling at the posted speed limit of 6.70 m/s (15 miles/h) in a school zone. The car passing a school bus when a child darts out from in front of the bus. The car is 10.0 m from the child when the driver of the car applies the brakes. The car decelerates at a constant rate of 4.00 m/s2 until coming to a halt. Calculate the

(a) distance of the car travels while decelerating and

(b) distance required to stop if the car is initially traveling at 13.4 m/s (30.0 miles/h).

+5

Answers (1)

Know the Answer?

Edgar Ward · Answer 1

Answer: 5.6m and 22.4m

Explanation: from the 3rd equation of motion

v²=u²+2as

v²-u²=2as where : v=0 u=6.7m/s a=4m/s² s=?

0-6.7²=2*4*s

44.89=8s

s=44.89:8

s=5.6m

for the second part, we shall still make use of the same equation.

v²-u²=2as where: a=4m/s² u=13.4m/s v=0 s=?

0-13.4²=2*4*s

179.56=8s

s=179.56/8

22.4m