What is the recommended amount of time that a teenager should be participating in physical activity

A: 30 min

B: 60 min

C: 45 min

D: 15 min

Two children, Ahmed and Jacques, ride on a merry-go-round. Ahmed is at a greater distance from the axis of rotation than Jacques. Which of the following are true statements? (There could be more than one correct choice.) Choose all that apply.

An object initially at rest explodes in two fragments of masses 5 kg and 7.5 kg that move in diametrically opposite directions. If the speed of the first fragment is 8.1 m/s, find the internal energy of the explosion.

According to the law of conservation of charge which statement can be true? A) A metal rod lost charge. B) A silk cloth gained charge. C) Charges are created from nothing. D) Charge moved from hair to a balloon.

Which statement is true about additional force being applied to an object in motion? A. if an object is in motion and more force is applied in the direction of its motion, the object will remain at a constant speed. B.

Which of these describe the composition of earths atmosphere? A) mixture B) substance C) compound

If a spacecraft that seems to be motionless in deep space is given some type of quick push, what will happen? A. The spacecraft will not move because it only works on earth. B.

A fast, white water cascade is also known as what?

What is a stack of membranes that packages chemicals

Under what condition (s) will an object be in equilibrium? Notice that equilibrium in physics has a broader definition. (A) Only if it is moving with constant velocity. (B) Only if it is at rest.

If a pressure gauge measure an increase in 3*10^ (5) Pa on an area of 0.7 m^2, calculate the increase in the force applied to the area?