Hardness and density are physical properties.

a. True

b. False

You are going to turn a screw using a wrench. will the work you do on the wrench be more or less than the work done by the wrench to the screw

You have two rods A and B, both made of a nonconducting material. Initially, neither rod is charged. A sphere carrying 100 units of surplus positive charge is placed close to the left end of rod A.

Why are infrared telescopes useful for exploring the structure of the galaxy? why is it important to make observations at both near-infrared and far-infrared wavelengths?

Cosmic ray particles can do permanent damage to DNA, especially if both strands are damaged. Explain why damage to just one base on one strand of a DNA molecule may be repairable.

In a non-electronic small engine ignition system which of the following ignition components is energized by the power source first

For a projectile launched from the vertically from the surface the earth with initial velocity v0, the velocity of the projectile when at distance r from the center of the earth satisifes the equation: v^2 =

What is the formula for convection?

A 398-kg boat is sailing 14.0° north of east at a speed of 1.50 m/s. 23.0 s later, it is sailing 33.0° north of east at a speed of 4.40 m/s. During this time, three forces act on the boat: a 32.8-N force directed 14.

You use sunglasses to reduce the glare of the sun when you go outside. You are taking advantages of light's ability to do which of the following? Possible Answers: to reflect to refract to diffract to polarize

Is light made of elements and atoms