Question

The speed of a car weighing 1300 kg increases from 36 km/h to 72 km/h uniformly. What will be the change in momentum of the car? *

a] 13000 kg km/h
b] 13000 kg m/s
c] 36000 kg m/s
d] 36000 g m/s

Answer 1

$\huge{\underline{\underline{\tt{\pink{Given}}}}}\:$

The speed of a car weighing 1300 kg increases from 36 km/h to 72 km/h uniformly.

$\huge{\underline{\underline{\tt{\blue{To\: Find}}}}}\:$

What will be the change in momentum of the car?

$\huge{\underline{\underline{\tt{\red{Solution}}}}}\:$

Mass of the car ${\boxed{\green{=\: 1300 \:kg}}}$

Intial velocity ${\boxed{\green{\: = \:36\: km / h}}}$

Final velocity ${\boxed{\green{=\: 72\: km / h}}}$

We know that Momentum = p = mv

where , p = momentum

m = the mass

v = velocity

Change in momentum = mv - mu

= 1300 × 72 - 1300 × 36

= 1300 ( 72 - 36 )

= 1300 × 36

${\boxed{\orange{= \:46800 \:kg \:km / h }}}$

Converting units km / h into m / s

$\implies\:46800\:\times\:\dfrac{5}{18}$

$\implies\:\dfrac{234000}{18}$

${\boxed{\purple{13000\:kg\:m/s}}}$