Một vật được thả rơi từ độ cao 20m xuống đất. Lấy g = 10m/s^2. a/ Sao bao lâu vật rơi chạm đất?
b/ Tìm độ lớn vận tốc lúc vật vừa chạm mặt đất?
c/ Tìm quãng đường vật rơi được sau 1 giây kể từ lúc thả?

In a vernier instrument the main scale is in 1/2 mm divisions .vernier is made by redividing 19 such divisions into 20 equal parts. calculate the least count of the instrument.

The 5-kg cylinder is initially at rest when it is placed in contact with the wall b and the rotor at a. if the rotor always maintains a constant clockwise angular velocity v = 6 rad> s, determine the initial angular acceleration of the cylinder. the coefficient of kinetic friction at the contacting surfaces b and c is mk = 0.2.

Which is special about a dc circuit ? a. it has both series and parallel components b. it has only series or only parallel components c. charge moves in a single direction d. charge moves back and forth quickly