OCR A Physics A-level Topic 5.3: Circular Motion

2π

rads^-1

divide by 360 and multiply by 2π

<p>the time taken for an object to travel a full circle</p> Signup and view all the answers

<p>f = 1/T</p> Signup and view all the answers

<p>ω = θ/t</p> Signup and view all the answers

<p>Because its direction is constantly changing</p> Signup and view all the answers

<p>causing the change in direction of an object moving in a circle</p> Signup and view all the answers

<p>ω = 2π/T</p> Signup and view all the answers

<p>Centripetal force</p> Signup and view all the answers

<p>v = 2πr / t or v = ωr</p> Signup and view all the answers

<p>The rate of change of velocity</p> Signup and view all the answers

<p>a = v² / r or a = ω²r</p> Signup and view all the answers

<p>F = mv² / r or F = mω²r</p> Signup and view all the answers

<p>Gravitational fields, friction, tension in a rope, and others</p> Signup and view all the answers

<p>Because the centripetal force is the net force acting towards the centre of the circle</p> Signup and view all the answers

<p>Tying a bung to a piece of string and threading it through a glass tube, with a weight suspended from the other end</p> Signup and view all the answers

<p>To provide the centripetal force</p> Signup and view all the answers

<p>Perpendicular to the direction of the velocity, towards the centre of the circle.</p> Signup and view all the answers

<p>The speed is equal to the angular velocity multiplied by the radius.</p> Signup and view all the answers

<p>The centripetal force is directly proportional to the mass of the object.</p> Signup and view all the answers

<p>The centripetal force would decrease.</p> Signup and view all the answers

<p>No, the centripetal force cannot be zero.</p> Signup and view all the answers

<p>The bung is the object moving in a circular path.</p> Signup and view all the answers

<p>The centripetal acceleration is equal to the rate of change of velocity.</p> Signup and view all the answers

<p>The glass tube keeps the string vertical, ensuring the force of gravity acts downwards.</p> Signup and view all the answers

<p>It is important to consider the resultant force because multiple forces may be acting on the object.</p> Signup and view all the answers

<p>Radians can be used directly in calculations, as they are defined in terms of the radius of the circle, making them a more fundamental and natural unit for measuring angles.</p> Signup and view all the answers

<p>The angular velocity is doubled, as ω = 2π/T, so if T is halved, ω is doubled.</p> Signup and view all the answers

<p>The centripetal force is directed towards the centre of the circle, which causes the object to change direction and move in a circular path.</p> Signup and view all the answers

<p>The frequency is equal to the number of full circles completed in one second.</p> Signup and view all the answers

<p>The angular velocity is constant because the rate of change of angle is constant, even though the direction of the velocity is changing.</p> Signup and view all the answers

<p>The radius is used to define the radian, which is the unit of measurement for angular velocity.</p> Signup and view all the answers

<p>The centripetal force causes the object to change direction and move in a circular path, rather than moving in a straight line.</p> Signup and view all the answers

<p>The unit of measurement for the period is seconds.</p> Signup and view all the answers

<p>The angular velocity is important because it describes the rate of change of angle, which is a fundamental aspect of circular motion.</p> Signup and view all the answers

<p>The object must be accelerating, and this acceleration is provided by the centripetal force.</p> Signup and view all the answers

<p>v = ωr</p> Signup and view all the answers

<p>Towards the centre of the circle.</p> Signup and view all the answers

<p>F = m(v^2)/r</p> Signup and view all the answers

<p>To provide a smooth surface for the string to move through.</p> Signup and view all the answers

<p>The centripetal force decreases.</p> Signup and view all the answers

<p>It is necessary to consider the resultant force because centripetal force is the net force acting towards the centre of the circle.</p> Signup and view all the answers

<p>ω = 2π/T</p> Signup and view all the answers

<p>It provides the necessary acceleration towards the centre of the circle.</p> Signup and view all the answers

<p>The angular velocity represents the rate of change of angle of an object moving in a circle.</p> Signup and view all the answers

<p>The angular velocity is inversely proportional to the period of the object.</p> Signup and view all the answers

<p>The velocity is constantly changing direction, while the speed may remain constant.</p> Signup and view all the answers

<p>The centripetal force is necessary to change the direction of the object's velocity and maintain its circular motion.</p> Signup and view all the answers

<p>The conversion to radians simplifies calculations involving angular velocity and frequency.</p> Signup and view all the answers

<p>The frequency is the number of full circles completed in one second.</p> Signup and view all the answers

<p>The angular velocity decreases as the radius of the circle increases.</p> Signup and view all the answers

<p>The centripetal force acts perpendicular to the direction of the velocity, towards the centre of the circle.</p> Signup and view all the answers

<p>The unit of measurement for angular velocity is radian per second (rads-1).</p> Signup and view all the answers