Question

I really need help with these questions. Thanks in advance!

1. The speed of light in water is three fourths the speed of light. Compute the index of refraction of water.

2.How far must a girl stand in front of a concave spherical mirror of radius 120 cm to see an image of her four times its natural size?

3.How much heat (in kiloCalories) is required to change 10 g of ice at 0 degrees to steam at 100 degrees Celsius.

Answer 1

So u hv 3 questions

Answer 2

For question 1

Answer 3

Do u know the formula which is related with velocity of light nd refractive ndex