# Science Check

posted by .

1)Two balls having the same mass of 1 kg roll toward each other, each moving at the same speed of 1 m/s. What is the combinded momentum?

Would it be 0 kg m/s

2)A 30 kg girl and a 25kg boy face each other on friction free roller blades. The girl pushes the boy who moves away at 1 m/s. The girls speed is?

Would it be .45

3)The power extended when a 10 N barbell is raised 2.0 m in 2 s is _____ watts
would it be 40?

4)Car A travels for times as fast as Car B. When braking to a stop Car A skids____ times as far as car B.

16?

(1) yes
(2) no. 30*Vgirl = -25*Vboy
Solve for Vgirl when Vboy = 1
(3) no. DIVIDE the work by the time
(4) yes. 4^2 = 16 Do you know why the skid is proportional to the square of speed? It has to do with kinetic energy

• Science Check -

would it be 55

## Similar Questions

1. ### Science

Two masses of 20 and 10 kg are moving in the same direction and one directly behind the other. The 20-kg mass is behind and moving at 10m/s and the other is moving at 5m/s. The masses collide and after the collison, the 20kg mass moves …

1) Two identical automobiles have the same speed, one traveling east and one traveling west. Do these cars have the same momentum?
3. ### physics

Which one of the following statements is true for two bodies having same kinetic energy but different masses?
4. ### physics

A compact car, mass 705 kg, is moving at 1.00 102 km/h toward the east. Sketch the moving car. Do this on paper. Your instructor may ask you to turn in this work.. (a) Find the magnitude and direction of its momentum. Draw an arrow …
5. ### physics

Two identical balls are moving at the same speed of 3 m/s toward each other. With no external forces acting, what would be the magnitude (value) of the total momentum of the two balls after collision?
6. ### Physics -Conservation of Momentum-

1) A 1 kg mass moving at 1 m/s has a totally inelastic collision with a 0.7 kg mass. What is the speed of the resulting combined mass after the collision?
7. ### Physics -Conservation of Momentum-

1) A 1 kg mass moving at 1 m/s has a totally inelastic collision with a 0.7 kg mass. What is the speed of the resulting combined mass after the collision?
8. ### Physics (MOMENTUM)

Please, help me answer this question. Two balls are moving in the same direction. Ball A has half the mass of ball B, and is moving at twice its speed. (a) Which ball has the greater momentum?
9. ### science

In the diagram above, the arrows represent momentum. A larger arrow indicates more momentum. Which of the following best describes how the balls will move after ball A collides with ball B?