The focal length is the distance from the middle of the lens to the what?

Which describes refraction

Y=1/2 at^2 solve for t

The source of the magnetic field on the Sun is

3. If substance A has half the index of refraction of substance B, which is (most likely) more dense

A sound wave in the air has a frequency of 680 cycles per second. What is the approximate wavelength of the sound wave

An olympic hurdler accelerates at a rate of 15.5 m/s2. what is the rate in miles/min2?

What is the conservation of energy?

What data are needed to calculate the actual mechanical advantage of a machine

What antenna length should be used to create a dipole antenna that emits 100-mhz electromagnetic waves, a frequency typical of fm radio broadcasts?

If a motor lifts a 400.-kilogram mass a vertical distance of 10. meters in 8.0 seconds, the minimum power generated by the motor is (1) 3.2 * 10^2 W (3) 4.9 * 10^3 W (2) 5.0 * 10^2 W (4) 3.2 * 10^4 W