Which of the following is a physical change?

A.) sawing a piece of wood.

B.) burning a piece of wood.

C.) rust forming on an iron fence.

D.) a copper roof changing color from green to red.

Density is the ratio of an object's mass to its volume. would you expect density to be a vector or a scalar quantity? explain.

What is Conservation Momentum

A particle moves along a straight line and its position at time t is given by s (t) = 2t^3-24t^2+90t t>=0 where s is measured in feet and t in seconds.

Which option correctly defines a generator? 1. a device that converts thermal energy into mechanical energy 2. a device that converts light energy into electrical energy 3. a device that converts electrical energy into mechanical energy 4.

A digital speedometer constantly reads zero mph. Technician A says the problem may be the vehicle speed sensor. Technician B says the problem may be the throttle position sensor. Who is correct

Which solid is the best thermal insulator A. brass b. ice C. styrofoam D. copper

When a high-mass star explodes, which of the following is left over in the center? A. Black hole B. Neutron star C. White Dwarf D. either a or b

Which object is an insulator?

Whats the difference between population density and population size?

A standing wave is established in an organ pipe that is closed at one end. What is located at the open and closed ends of the pipe?