An iron nail floats in mercury and sinks in water. Explain why?

In a lab environment, you are investigating the impulse of a force exerted on a brick when the brick's speed is reduced from 2.5 m/s to a complete stop.

Suppose you have two meter sticks, one made of steel and one made of invar (an alloy of iron and nickel), which are the same length (1.00 m) at 0°C. The coefficients of volume expansion for steel and invar are 3.6 * 10-5 / °C and 2.

If a 1.5 v battery sends a current through a 50 resistor, the current is:

Two masses traveling at the same speed v₀ collide head on. Nothing is known about the collision other than that it is not completely inelastic. True / False.

A passenger in the rear seat of a car moving at a steady speed is at rest relative to a. the side of the road. b. a pedestrian on the corner ahead. c. the front seat of the car. d. the wheels of the car.

Which planet, when viewed through a telescope, appears as a reddish ball interrupted by some permanent dark regions that change intensity?

A wave has a wavelength of 10 mm and a frequency of 5 hertz. What is its speed? a. 50 mm/s b. 50 hertz's c. 2 mms d. 0 0.50 mms

Suppose you illuminate two thin slits by monochromatic coherent light in air and find that they produce their first interference minima at / pm 35.09 degrees on either side of the central bright spot.

Tala wants to create a sound echo. She can create the echo using a pane of glass or a carpet square. Which one does she choose? Explain.

a the average distance from the Sun to Pluto is approximately 6.10 x 1 0 ^9. how long does it take light from the sun to reach Pluto?