What's heavier a pound of feathers or a pound of stones?

A dart is loaded into a spring-loaded toy dart gun by pushing the spring in by a distance d. for the next loading, the spring is compressed a distance 2d. how much work is required to load the second dart compared to that required to load the first?

Powered and rotating type concrete troweling machines that are manually guided shall be equipped with a control switch that will automatically shut off power whenever hands of the operator are removed from equipment handles. True or False?

Monochromatic electromagnetic radiation illuminates an area of a surface. The electric and magnetic fields of the waves are then doubled in magnitude.

A 2.0-kg ball rolls to the right at 3.0 m/s. A 4.0-kg ball rolls to the left at 2.0 m/s. What is the momentum of the system after a head-on collision of the two balls?

A 1.31 kg flower pot falls from a window. What is the momentum of the pot when it has fallen far enough to have a velocity of 2.86m/s? 00.458 kgm/s 06.35 kgm/s O 3.75 kgm/s 02.18 kgm/s

Why is accuracy important in dodgeball?

A pipe has a length of 1.29 m. Determine the frequency of the first harmonic if the pipe is open at each end. The velocity of sound in air is 343 m/s. Answer in units of Hz.

The half-life of plutonium-238 is 87.7 years. What percentage of the atoms in a sample of plutonium-238 will remain radioactive after 263.

Charge q is 1 unit of distance away from the source charge S. Charge p is four times further away. The force exerted between S and q is ___ the force exerted between S and p. 1/4 1/16 16 times 4 times

A 21.7kg child descends a slide 3.5 m high and reaches the bottom with a speed of 2.2m/s. How much thermal energy due to friction was generated in this process?