Question

1. a) A driver is sitting in a truck whose total mass (including driver) is 4500 kg. In starting from rest, the truck's engine exerts a force through its tires) of 16,200 N. What is the truck's acceleration ? Acceleration The driver's mass is 60 kg. Assuming the driver is firmly attached to her seat, what force must the seal produce to cause her to move with (inside) the truck during this time? Force (driver) 2. a) Two blocks on wheels are together as shown. Block A has a spring Inside which can exert a 250 N force on Block B Block A has a mass of 55kg, and Block Bhas a mass of 40 kg. direction on drawing What is the acceleration of Block B after the spring is released ? Note Accel (Block A) What is the acceleration, if any of Block A? Accel (Block B) The astronaut then travels to Mars where N "-9.8 m onth b) An astronaut in a space suit has a weight on Earth of 600 N the acceleration due to gravity now is 3.7 m/ ? What is the astronaut's mass? Mass What is the astronaut's weight on Mars? Weight on Mars 3. A centrifuge is a device which spins very fast producing accelerations and associated forces a) A centrifuge is able to produce 1500"'" (Earth 's of acceleration due to its circular motion. What would be the speed of some material which was located a radial distance of 3.5 cm from the center of the centrifuge Speed b) Suppose the material above contained two liquid masses, one 4.5 grams and the other 4.6 grams. What would be the difference in forces acting on the two different masses? (base unit of mass?) Diff. of Forces

Answer 1

Given: Mass of driver and truck = 4500 kg Initial velocity of truck = 0 Force exerting on truck = 16,200 N Acceleration of the truck can be calculated as: 16,200 N 4500 kg a=3.6 m/s2 Mass of driver = 60 kg Acceleration of the truck = acceleration of the seat Therefore, acceleration of seat = 3.6 m/s2 Force on driver,

F, = mga F, =60x3.6 F, = 216 N