Question

A car accelerates with a constant acceleration of 1.2 m/s^2 along a long straight road. How long does it take the car to accelerate from 100 kph to 110 kph, and how far does it travel while doing so? [Hint: watch your units and your significant figures. Because there is no other information, take the speeds as three significant figures.] It takes ______ seconds to accelerate to 110 kph. While accelerating, the car travels _____ m. Separate your answers with a comma. Example: a, b

Answer 1

ans == 2.32 sec, 67.68mt.

Explanation:

100 kph=100×1000/3600=27.78 m/s

110 kph=110×1000/3600= 30.56 m/s

so, change in velo. =(30.56 -27.78) m/s

=2.78 m/s (approx)

so time taken ,t= 2.78/1.2 sec

=2.32 sec (approx)

now during this time car travels =(27.78 ×2.32+1/2×1.2×2.32×2.32)

=67.68 m.(approx)

so ans == 2.32 sec, 67.68mt.