Answer:
24.4
Explanation:
cup has 0.20 joule of kinetic energy when it hits
the floor, what is the total amount of energy
converted into internal (thermal) energy during
the cup’s fall?
(1) 0.02 J (3) 2.2 J
(2) 0.22 J (4) 220 J
Answer:
They collide, couple together, and roll away in the direction thatthe 2m/s car was rolling in.
Explanation:
We should start off with stating that the conservation of momentum is used here.
Momentum = mass * speed
Since, mass of both freight cars is the same, the speed determines which has more momentum.
Thus, the momentum of the 2 m/s freight car is twice that of the 1 m/s freight car.
The final speed is calculated as below:
mass * (velocity of first freight car) + mass * (velocity of second freight car) = (mass of both freight cars) * final velocity
(m * V1) + (m * V2) = (2m * V)
Let's substitute the velocities 1m/s for the first car, and - 2m/s for the second. (since the second is opposite in direction)
We get:
solving this we get:
V = - 0.5 m/s
Thus we can see that both cars will roll away in the direction that the 2 m/s car was going in. (because of the negative sign in the answer)
A. 30cm. B. 40cm. C. 20cm. D. 60cm.
Answer:
Quan sát sóng dừng trên sợi dây dài 60cm cố định hai đầu, thấy có 3 nút (bao gồm cả hai
nút hai đầu) và 2 bụng. Bước sóng của sóng lan truyền trên sợi dây là: