Apolice car on the side of the road (at rest) uses a radar gun to catch speeders as they approach it. the frequency the radar gun emits is 8 x 109 hz and the speed limit is 65 mi/hr. what is the difference in frequency of the emitted and returned radar wave

How many seconds does it take a pebble released from rest off a bridge to fall 29.4 m ? what is the pebble's speed when it has fallen 29.4 m ?

The energy released by a chemical reaction can be measured using a calorimeter. when barium hydroxide octahydrate crystals are reacted with dry ammonium chloride inside of a coffee cup calorimeter, the temperature of the 18.00 g of water in the calorimeter decreases from 30.0°c to 8.0°c. the equation for calculating energy absorbed or released by a reaction is: where q is the energy released or absorbed, m is the mass of water in the calorimeter, cp is the specific heat of water, and δt is the observed temperature change. if the specific heat of liquid water is 4.19 j/g·°c, how much energy was absorbed by the reaction?

What is the average speed of a car that travels 40 mph for 1 hour and 60 mph in another hour?