CCM2 Day 6

Knight’s Charge Day 5 1/27/15

1) Hooke’s Law for an elastic spring states that the distance a spring stretches varies directly as the force applied. If a force of 160 newtons stretches a spring 5 cm, how much will a force of 368 newtons stretch the same spring?

2) The intensity of light produced by a light source varies inversely as the square of the distance from the source. If the intensity of light produced 3 feet from a light source is 750 foot-candles, find the intensity of light produced 5 feet from the same source.

Check Homework

JOINT Variation

If p varies jointly as q and r squared, and p = 225 when q = 4 and r = 3, find p when q = 6 and r = 8.

JOINT Variation

Kinetic energy varies jointly as the mass and the square of the velocity. A mass of 8 grams and a velocity of 5 centimeters per second has a kinetic energy of 100 ergs. Find the kinetic energy for a mass of 6 grams and a velocity of 9 centimeters per second.

JOINT Variation

The volume of wood in a tree (V) varies directly as the height (h) and inversely as the square of the girth (g). If the volume of a tree is 144 cubic meters when the height is 20 meters and the girth is 1.5 meters, what is the height of a tree with a volume of 1000 and girth of 2 meters?

Practice

Victory Lap

1) If p varies directly as the square of q, and p = 20 when q = 5, find p when q = 8.

2) The volume of gas in a container at a constant temperature varies inversely as the pressure. If the volume is 32 cubic centimeters at a pressure of 8 pounds, find the pressure when the volume is 60 cubic centimeters.