This physics problem tests your understanding of fundamental physical laws and their applications. The step-by-step solution below breaks down the problem using relevant equations and physical reasoning.
ScanSolve AI Answer
Here are the solutions to the problems. Problem 1: A body of mass 5 kg is placed in a lift. Find the reaction between the floor of the lift and the body when the lift moves upward: i) at constant velocity ii) with an acceleration of 2.5 m s^-2 (take g = 10 m s^-2) The general formula for the reaction force R when a lift moves upward with acceleration a is R = m(g+a). a) When the lift moves upward at constant velocity: Step 1: Identify the given values. The mass of the body is m = 5 kg. The acceleration due to gravity is g = 10 m s^-2. Since the velocity is constant, the acceleration of the lift is a = 0 m s^-2. Step 2: Substitute the values into the formula. R = m(g+a) R = 5 kg (10 m s^-2 + 0 m s^-2) R = 5 kg × 10 m s^-2 R = 50 N The reaction force is 50 N. b) When the lift moves upward with an acceleration of 2.5 m s^-2: Step 1: Identify the given values. The mass of the body is m = 5 kg. The acceleration due to gravity is g = 10 m s^-2. The acceleration of the lift is a = 2.5 m s^-2. Step 2: Substitute the values into the formula. R = m(g+a) R = 5 kg (10 m s^-2 + 2.5 m s^-2) R = 5 kg × 12.5 m s^-2 R = 62.5 N The reaction force is 62.5 N. Problem 2: A body of mass 5 kg is placed in a lift. If the lift moves upward with a retardation of 2 m s^-2, find the reaction between the floor of the lift and the body (take g = 9.8 m s^-2). When a lift moves upward with retardation (deceleration), the effective acceleration is downwards. The formula for the reaction force R becomes R = m(g-a), where a is the magnitude of the retardation. Step 1: Identify the given values. The mass of the body is m = 5 kg. The acceleration due to gravity is g = 9.8 m s^-2. The retardation of the lift is a = 2 m s^-2. Step 2: Substitute the values into the formula. R = m(g-a) R = 5 kg (9.8 m s^-2 - 2 m s^-2) R = 5 kg × 7.8 m s^-2 R = 39 N The reaction force is 39 N. Send me the next one 📸