body of mass 5kg moves on the substrate under the action of a force of 40N. The force acts on the body of 60 ° in relation to the substrate. How much acceleration does the body get if we ignore the friction. What is the reaction force of the substrate​

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)