Prove if this is dimensionally correct. 1/2mv² = 1/2mv² + √mgh​

Ahot-air balloon takes off from the ground traveling vertically with a constant upward acceleration of magnitude g/4. after time interval δt, a crew member releases a ballast sandbag from the basket attached to the balloon. how many seconds does it take the sandbag to reach the ground? (express your answer in terms of δt)

Suppose astronomers built a 140-meter telescope. how much greater would its light-collecting area be than that of the 10-meter keck telescope? express your answer using two sign

Abody covers a semicircle of radius 7cm in 5s .find its linear speed