Question

an object of mass 2 kg is dropped from a certain height then work done by gravity in 4 sec is: (g=10ms/s²)​

Answer 1

Answer:

using s= ut +1/2 at^2 we have

s = 1/2 ( 10)(16)= 80m  ( u= 0 as particle drop from rest)

now work dome = F.s = mg . s = 2 *10 * 80 = 1600J

Explanation:

Answer 2

Explanation:

WORK =FORCE× DISPLACEMENT, WE KNOW FORCE = Mass×acceleration, Given :mass=2kg,acceleration =10m/s^2, acceleration = velocity/time, 10= v/4,v=10m/s2^×4s=40m/s, now we know velocity =displacement/time,displacement =v×t=40×4=160, work =f ×d=2000gm×10m/s^2×160m=64 ×10^5= gmm^2s^2