A block of mass m = 3.7 kg slides from left to right across a frictionless surface withra speed v; - 7.4 m/s. It collides in a perfectly elastic collision with a second block of mass M that is at rest. After the collision, the 3.7-kg block reverses direction, and its new speed is vf 2.2 m/s. What is M?

8.9 kg
6.8 kg
5.2 kg
7.5 kg

Will give brainliest! jay rides his 2.0-kg skateboard. he is moving at speed 5.8 m/s when he pushes off the board and continues to move forward in the air at 5.4 m/s. the board now goes forward at 13 m/s.a. determine jay’s mass.b. determine the change in the internal energy of the system during this process.(express your answer to two significant figures and include the appropriate units.)

Aperson walking 1 mile everyday for exercise, leaving her front porch at 9: 00 am and returning to her front porch at 9: 25 am. what is the total displacement of her daily walk? a) 1 mileb) 0c) 25 minutes d) none of the above

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