Q. Express 1 inch in meters
solution:- By definition, 1 inch=2.54 cm(exactly)
=(2.54/100) m
=0.0254 m(exactly)
Q.If l=0.90 m ,g=10 m/s^2 ,find the value of √(l/g).
solution:- √(l/g)
=√(0.90 m/10 m/S^2)
=0.3 s
Q.The amount of energy needed to melt 1 gram of ice is 80 calories.How many joules of energy will be needed to melt 1 kg of ice?
solution:- 1 kg =1000 g.
The energy neede to melt 1 kg of ice is therefore
(80 calories)×1000=8000 calories.
Now, 1 calories=4.186 J.
so,8000 calories =8000×4.186 j=3.3488 × 10^5 J