Question

$\huge\red{զմҽsԵíօղ}$
a force of 20N acts on a body of 2kg for 3 seconds .find the kinetic energy in 3 seconds.


✦∂σɳ'ƭ รραɱ​

Answer 1

$\huge\red{αɳรωεɾ}$

Force = mass × acceleration

F=10N

m=2kg

then,

$a = \frac{F}{m} = \frac{10}{2} = 5m/ {s}^{2}$

(i)Now,

u=0

t=3sec

v = u + at = 0 + 3 × 5 = 15m/s

(ii) Initial momentum = mu =2×0=0

Final momentum = mv = 2×15=30kg − m/s

Change in momentum = Final momentum - Initial momentum

= 30 − 0 = 30kg − m/s

Answer 2

Answer:

Force = mass × acceleration

F=10N

m=2kg

then,

(i)Now,

u=0

t=3sec

v = u + at = 0 + 3 × 5 = 15m/s

(ii) Initial momentum = mu =2×0=0

Final momentum = mv = 2×15=30kg − m/s

Change in momentum = Final momentum - Initial momentum

= 30 − 0 = 30kg − m/s