Answer Happy

1. 2. 3. 4. 5. A model rocket of mass 3.0 kg has an engine which can exert a thrust of 178.0 N. The rocket starts from rest on a launch pad at the surface of the earth and the engine fires for a period of 19.0 s, so the rocket moves straight upwards. (Don't forget the FBD) a. Find the weight of the model rocket. b. Calculate the acceleration of the rocket as it leaves the launch pad. c. How high has the rocket climbed after the engine has fired? A block of mass 3.3 kg is pushed with a horizontal applied force of 39.0 N across a horizontal surface. The coefficient of friction between the block and the surface is μ = 0.84 a. Find the frictional force acting on the block. b. Find the acceleration of the block. c. If the block starts from rest, how long does it take to move 80.0 m? A person of mass 78.0 kg is in an elevator, resting on a scale. a. If the reading on the scale is 1357 N, find the acceleration of the elevator. (Don't forget the direction of acceleration) b. What is the reading on the scale when the elevator accelerates downwards at 2.9 m/s²? A block of mass 19.0 kg is hanging by a string which passes over a pulley to another mass of 41.0 kg. a. Find the acceleration of the system when released. b. Find the tension in the string as the system moves. A block of mass 5.1 kg is pulled across a horizontal surface by an applied force of 30.0 N which is acting at an angle of 24.0° from the horizontal (pulling upward). The coefficient of kinetic friction between the block and the horizontal surface is u-0.24. (Hint: use horizontal and vertical components of the applied force separately) a. Find the normal force between the horizontal surface and the block. b. Calculate the force of kinetic friction acting on the block.(assume the block starts) c. Find the acceleration of the block as it moves horizontally across the floor.