Physics Chapter 8: Force and Motion

push, hit or pull

muscular effort

effect of a force

<p>Galileo Galilei and Isaac Newton</p> Signup and view all the answers

<p>rest</p> Signup and view all the answers

<p>motion along a straight line</p> Signup and view all the answers

<p>Safety belts are worn in vehicles to prevent accidents caused by sudden stops, starts, or collisions with panels in front. They exert a force on our body to make forward motion slower.</p> Signup and view all the answers

<p>Passengers tend to fall backwards in a bus when it starts moving suddenly because the sudden start brings motion to the bus and their feet in contact with the floor, while the rest of the body opposes this motion due to inertia.</p> Signup and view all the answers

<p>Passengers tend to get thrown to one side when a motorcar makes a sharp turn at high speed due to their inertia. The unbalanced force applied by the engine to change the direction of motion causes the passengers to slip to one side of the seat.</p> Signup and view all the answers

<p>The law of inertia can be illustrated by making a pile of carom coins on a table and attempting a sharp horizontal hit at the bottom of the pile. The inertia of the coins causes them to 'fall' vertically on the table once the lowest coin is removed.</p> Signup and view all the answers

<p>When a fast-moving coin hits the bottom of the carom pile, the bottom coin moves out quickly due to the impact. The inertia of the other coins makes them fall vertically on the table after the bottom coin is removed.</p> Signup and view all the answers

<p>A body remains at rest unless acted upon by an unbalanced force due to the property of inertia. Inertia causes objects to resist changes in their state of motion.</p> Signup and view all the answers

<p>kilogram-metre per second (kg m s-1)</p> Signup and view all the answers

<p>Magnitude of force and time during which the force is exerted.</p> Signup and view all the answers

<p>A continuous push results in a gradual acceleration of the car to the required speed.</p> Signup and view all the answers

<p>The rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of force.</p> Signup and view all the answers

<p>Impulse is the change in momentum of an object due to the force applied over a period of time.</p> Signup and view all the answers

<p>The force necessary to change momentum depends on the time rate at which the momentum is changed.</p> Signup and view all the answers