Rotatory motion - when an object moves on a fixed axis Circular motion -when an object moves in a circular path . Eg the car in first animation { where we apply formula of circumference of circle - 2πr }
Nice sir. Your question answer, Ans:-(1)ceiling fan is performing rotational motion, but the blade of ceiling fan performing circular motion. Ans:-(2)satellite moving around the earth is an example of circular motion.
But sir earth moves around the sun in an elliptical path then how it can exhibit circular motion while revolving around the sun, the motion should be elliptical. And sir another question that if there is some distance between COM axis and rotational axis of body then it will exhibit circular motion is this also true that if there is some distance between centre of gravity and axis of rotation,will the body execute circular motion or not in that case?
Hi Binayak, Very good question. The circle is a special case of an ellipse in which 2 focii meet called the center of the circle. In reality, it is very difficult to find the perfect circular motion. If I consider the Sun and the earth as a system then their center of mass lies somewhere in the center of the sun and the rotational axis passes through the earth. There is a distance between the 2. The body executes the circular motion. It is because of the other forces like a gravitational force between the earth and the moon that makes it elliptical in shape. When you exclude all the other forces and then consider 2 body system then it will become a circular motion. But again each and everything in this universe is affecting each other. In short, you can call it a circular motion when we exclude all the other forces acting on the earth. I hope I made my point clear. A very good question is raised by you. All the best. Yash:)
Yes, Shifa you're right..... But satellite motion is not pure circular motion. It also rotates about its axis. Therefore, it is both circular and rotational. Thank you for watching the video! Yash:)
Great question Deepak, In rotation, the center of mass of a body is fixed in one place. It means there is no translational motion. But in this case, the cm of the rod is performing translational motion and is maintaining the fixed distance from the axis of rotation that is the hinge. Hence it is a circular motion. Let me make it clear, The rod attached with the hinge is not going anywhere rather it is spinning in one place. When you take the hinge and the rod as one system then it is a rotational motion. But when you consider the movement of the rod, its center is in translational motion. Hence rod is in a circular motion. I hope it's clear. cm is moving = Circular cm is fixed = rotational Thank you Yash :)
@@YashKumar-mypage sir, cm mass is in circular motion no here? Hw can it be in translational motion.. So the motion of hands of a watch is in circular motion right?..
Hi Wajahat, The motion is broadly divided into 3 categories: 1. Translational motion (Linear, Circular, Random) 2. Rotational motion 3. Vibratory or Oscillatory motion The objects in motion can have more than 1 type of motion. Coming to your question, The cradle moves to and fro about its mean position. Hence, it is an oscillatory motion. Thanks for watching the video. Yash :)
Very interesting question:) In a circular motion when the object is moving at a uniform speed, it will have acceleration towards the center, resulting in force. This force makes zero angle with the radial vector, hence torque is zero. But when a body is circling with varying speed, it will have tangential acceleration in addition to the radial one. Now the angle between the radial vector and the net force is non-zero. Hence the body will experience the net torque. Thank you for watching the video.
Hi Anuradha, The motion that repeats itself after a regular interval of time is called Periodic Motion. While on the other hand When an object moves around its axis, like our earth spinning around its axis, it is called a rotational motion. The rotational motion can be periodic or non-periodic. This rotational motion becomes a periodic motion when it takes the same time to rotate once on its axis. Like our earth always takes 24 hours to complete one rotation. The rotational motion is non-periodic when the rotation time around the axis is different between 2 or more consecutive spins. I hope you got my point. Thankyou Anuradha for watching the video. Yash:)
