The material of permanent magnet is MCQ with Answer and Explanation

Explanation:
Time of flight T = 2u/g = 2×49/9.8 = 98/9.8 = 10 s. Up and down symmetric. Max height = u²/(2g) = 122.5 m.

Explanation:
In uniform circular motion, speed remains constant but direction changes, so velocity (vector) changes. There is centripetal acceleration towards centre, so acceleration is not zero. Kinetic energy = ½mv², depends on speed, so remains constant. Thus, only speed is constant.

Explanation:
1×8 + 1×4 + 0×2 + 1×1 = 13.