Question

A car traveling 85 km/h slows down at a constant 0.47 m/s^2 just by "letting up on the gas."​ Calculate the distance it travels during the first second. Express your answer to two significant figures and include the appropriate units. Calculate the distance it travels during the fifth second.

Answer 1

Step-by-step explanation:

u = 85 km / h = 23.61 m /s

Acceleration a = - 0.47 m /s²

Distance travelled in n th sec

S_n = u + ( 2t -1 )a/2

S_n is distance travelled in n th seond

Distance traveled in 1 st second

= 23.61 - .5 x .47

= 23.37 m

=23 m

Distance travelled when t = 5 th

= 23.61 - (2x5 -1)/2 x .47

= 23.61 - 4.5 x .47

23.61 -2.115

=21.495

21 m is distance travelled in 5 th second .