If the period of a simple pendulum is t and we increase its length so that it is four times longer, what will the new period be? t/4 it is unchanged. t/2 2t 4t

2T

Explanation:

The period of a simple pendulum is:

T = 2π √(L/g)

If L is increased by a factor of 4, then:

2π √(4L/g)

4π √(L/g)

2T

So the period is doubled.

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form

365.25 earth days are in the year of a light year