Question

An object of mass 20 kg is sliding with a constant velocity of 40 ms-1 on a frictionless horizontal table. The force required to keep the object moving with the same velocity is​

Answer 1

Answer:

Heat energy E=ms(T

2

−T

1

)

Heat required is E=900×50×(38−18)=900×10

3

J

So the time required by heater of power 500W to supply this amount of heat is

△t=

P

E

=

500

900×10

3

=1800 sec=30 min

Explanation:

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