Question

please answer 20 a and 21 b

Answer 1

The product of the mass and the velocity of an object is called as linear momentum. It determines the quantity of motion in a body.Its SI unit is kg m/s.
Now,
m=1.5 kg
u=15 m/s
g=10 m/s^2
t=2s
Then,
h=ut-1/2gt^2
=)h=15×2-1/2×10×2×2
=)h=30-20
=)h=10 m
then,

P.E.=mgh

=1.5×10×10

=150 J

Hope it helps u.

Answer 2

20 a (Ans)
Momentum :- The product of mass and velocity of an object is called Momentum....
The SI unit of momentum is kg m/sec sq.
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21 b (Ans)
Given:- m=1.5 kg
u=15m/s
g= 10m/sec sq.
t=2 seconds
For h we are using 2nd equation
i.e; h=ut+1/2gt^2
h=1.5×2+1/2×10×2×2
h= 15/10×2+1/2×10×4
h=3+5×4
h=3+20
h=23 metre
Now, PE=mgh
= 1.5×10×23
= 15×23
= 365 Joules...ans••••
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@Suhana###‼‼❤❤