Question

An object drop from a clifd falls with a constant acceleration of 10 m/s^2. Find it's speed 2 second after it was drop.

Answer 1

Answer:

speed after 2 seconds =5m/s

Explanation:

u=0m/s

a=10 m/s^2

t=2s

v=?

a=(v-u)/t

10=(v-0)/2

5=v

∴speed after 2 seconds =5m/s

Answer 2

Answer:

velocity=20 speed = 10

Explanation:

a=10 ms -2

u=0 ms -1

t= 2 sec

s=ut+1/2at²

s=0x2+ 1/2 (10x2²)

s= 1/2 x 10(4)            

s= 1/2 x 40

s=20 m          

v²-u²=2as

v²= 2(10)(20)

v²=   400

v=20 ms^-1

speed = 20/2

          = 10