Question

What is the velocity of an object of mass 1 kg which has 200 J of k.e.?
b. Calculate the p.e. of a 2 kg mass when it is
(i) 4 m, above the ground.
(ii) 6 m, above the ground. (g = 10 N/kg)

Answer 1

Answer:

a. 20m/s b.(i) 40J (ii) 60J

Explanation:

Here, we use kinetic and potential energy equations which bound gravity....

Hope u get it...

Answer 2

Answer:

a) 20m/s

b) (i) 80J

(ii) 120J

Explanation:

a) here mass = 1kg

kinetic energy = 200 J

so,

kinetic energy =1/2×mv²

200 =1/2×1×v²

200×2/1 = v²

400 =v²

20m/s =v

b) potential energy =mgh

mass =2kg

(I) height= 4m

gravity =10m/s²

P.E = mgh

= 2×10×4

= 20×4

= 80 Joules

(ii) height= 6m

mass = 2kg

gravity= 10m/s²

P.E = mgh

= 2×10×6

= 20×6

= 120 J