A boy kicks a football with a force of 20 N, the time the force acts for is 0.3s. Calculate the impulse on the ball.

Simple machines can a. increase force only b. decrease force only c. increase or decrease force

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?

Estimate the kinetic energy of mars with respect to the sun as the sum of two terms, that due to its daily rotation about its axis, and that due to its yearly revolution about the sun. (assume mars is a uniform sphere with mass = 6.4×10 to the power of 23 kg, radius = 3.4×10 to the power of 6 m, rotation period = 24.7 hours, orbital period = 686 days and is 2.3×10 to the power of 8 km from the sun.)