A 90kg boy and a 60kg girl, both wearing skates, face each other at rest on a skating rink. The boy pushes the girl, sending her eastward with a speed of 3 m/s.
Neglecting friction, determine the velocity of the boy. *
*
A) 8m/s
B) 2m/s
C) 3m/s
D) 7m/s

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?

Which of the following is an example of motion in two dimensions?

When a light bulb shines, it gives off light energy and energy. a. heat b. potential c. chemical d. electrical