03+Forces

Group 3

[|Google]

TASK:Describe how forces are measured and how they affect motion. Describe the difference between mass and weight and how they are measured. Describe the variables of momentum, how it is measured, and what affect it has on motion and energy.

 **FORCES** - measured in newtons (N) -- mass times acceleration - 4 types of forces (weakest to strongest): gravitational, electromagnetic, weak nuclear, strong nuclear - forces are vector quantities - weight is a force - equations: F = ma F = k [(q1 x q2)/d^2] EXAMPLE PROBLEM: A bullet with a mass of 48 g is fired from a gun. If the bullet leaves the gun with a force of 715 N, what is the acceleration of the bullet? m = 48 g or .048 kg a = x || F = ma || 715 = (.048)(x) x = 14895.8333 m/s^2 || 15,000 m/s^2 ||
 * //force://** push or pull, any influence that can cause an object to be accelerated
 * F = 715 N

or sluggishness, an object exhibits in response to any effort made to start it, stop it, or change in any other way its state of motion. - measured in grams or kilograms (metric) - the greater the mass, the greater the amount of matter in an object, and the greater the amount of inertia - mass is constant //EX) if an object has a mass of 5 kilograms on Earth, it will have a mass of 5 kilograms on the Moon//
 *  MASS **
 * //mass://** the quantity of matter in an object. More specifically, mass is the measurement of the inertia,

**WEIGHT** - measured in pounds (English system) or newtons (metric system) - weight changes (on different planets) //EX) if an object weighs 12 pounds on Earth, it will weigh about 2 pounds on the Moon//
 * //weight://** the gravitational force exerted on an object by the nearest most-massive body.

**MOMENTUM** - momentum is measured in kg*m/s - equation: P = mv //EX) a large truck with no brakes rolling down a hill has more momentum than a car moving at the same speed because the truck has more mass EX2) a large slow ship has a large momentum because it has a large mass EX3) a small fast bullet has a large momentum because of its high speed (velocity) EX4) a large truck that is not moving has no momentum because its velocity equals zero// EXAMPLE PROBLEM: If a car's mass is 1,200,000 g and its velocity is 14.0 m/s, what is its momentum? m = 1,200,000 g or 1,200 kg v = 14.0 m/s || P = mv || x = (1200)(14.0) x = 16,800 kg*m/s^2 || 17,000 kg*m/s || By: Elena DiMeo and Caroline Barry
 * //momentum://** the product of an object's mass and its velocity (inertia in motion)
 * P = x