Impulse is the change in momentum.
All we need is the momentum before and after.
Momentum = (mass) x (speed)
Before: = (80 kg) x (4.7 m/s) = 376 kg-m/s
After: = (80 kg) x (3.4 m/s) = 272 kg-m/s
Change in momentum = (376 - 272) = <span>104 kg-m/s
</span>Notice that when you work with impulse, you're USUALLY calculating
(force) x (time).
The force is in Newtons, and the time is in seconds,
so the impulse is usually in units of
Newton-seconds .
So how can I say that impulse and change of momentum are
the same thing ? Am I trying to pull a fast one on you ?
Remember that 1 Newton is 1 kg-m/s²
So (force) x (time)
= (Newton) x (second)
= (kg-m/s²) x (second) = kg-m/s .
and Momentum = (mass) x (speed) = (kg) x (m/s)
The units of impulse are the same as the units of momentum !
So when you give an object some impulse, you give it exactly
that much momentum.
Answer:
Explanation:
Given:
Initial velocity, vi = 26248 m/s
Final velocity, vf = 27000 m/s
Force, f = 7540 N
Mass, m = 2000 kg
Force = mass × acceleration
= mass × change in velocity/time
Change in velocity = vf - vi
Time, t = (2000 × (27000 - 26248))/7540
= 199.47 s.
I min = 60 sec
Tine, t = 3.325 min
= 3.33 min.