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प्रश्न
Earth moves around the sun with uniform velocity.
विकल्प
True
False
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उत्तर
This statement is false.
संबंधित प्रश्न
Read the statement below carefully and state, with reason, if it is true or false:
The acceleration vector of a particle in uniform circular motion averaged over one cycle is a null vector.
How does uniform circular motion differ from uniform linear motion?
Draw a neat labelled diagram for a particle moving in a circular path with a constant speed. In you diagram show the direction of velocity at any instant.
| A small pebble tied at one end of a string is placed near the periphery of a circular disc, at the centre of which the other end of the string is tied to a peg. The disc is rotating about an axis passing through its centre. |
- What will be your observation when you are standing outside the disc? Explain.
- What will be your observation when you are standing at the centre of the disc? Explain.
A uniform linear motion is unaccelerated, while a uniform circular motion is an accelerated motion.
A uniform metre rule of mass 100g is balanced on a fulcrum at mark 40cm by suspending an unknown mass m at the mark 20cm.
To which side the rule will tilt if the mass m is moved to the mark 10cm ?
Answer the following question.
Show that its time period is given by, 2π`sqrt((l cos theta)/("g"))` where l is the length of the string, θ is the angle that the string makes with the vertical, and g is the acceleration due to gravity.
A disc has mass 'M' and radius 'R'. How much tangential force should be applied to the rim of the disc, so as to rotate with angular velocity 'ω' in time t?
A string of length 'l' fixed at one end carries a mass 'm' at the other end. The string makes `3/pi` revolutions/second around the vertical axis through the fixed end as shown in figure. The tension 'T' in the string is ______.
Two particles P and Q are moving in concentric circles of rarui rp and rQ respectively. If their period of revolutions are in ratio 2 : 3, then ratio of their centripetal acceleration is ____________.
Earth also moves in circular orbit around sun once every year with on orbital radius of 1.5 × 1011 m. What is the acceleration of earth (or any object on the surface of the earth) towards the centre of the sun? How does this acceleration compare with g = 9.8 m/s2?
A small bead of mass m can move on a smooth circular wire (radius R) under the action of a force F = `"Km"/"r"^2` directed (r = position of bead r from P and K = constant) towards a point P within the circle at a distance R/2 from the centre. The minimum velocity should be ______ m/s of bead at the point of the wire nearest the centre of force (P) so that bead will complete the circle. (Take `"k"/(3"R")` = 8 unit)
A disc of radius 5 cm rolls on a horizontal surface with linear velocity v = 1`hat"i"` m/s and angular velocity 50 rad/s. Height of particle from ground on rim of disc which has velocity in vertical direction is ______ cm.
A wheel rotating at the same angular speed undergoes constant angular retardation. After the revolution, angular velocity reduces to half its initial value. It will make ______ revolution before stopping.
A ceiling fan rotates about its own axis with some angular velocity. When the fan is switched off the angular velocity becomes `(1/4)^"th"` of the original in time 't' and 'n' revolutions are made in that time. The number of revolutions made by the fan during the time interval between switch off and rest are ______. (Angular retardation is uniform)
Angular speed of hour hand of a clock in degree per second is ______.
A horizontal circular platform of mass M is rotating at angular velocity ω about a vertical axis passing through its centre. A boy of mass m is standing at the edge of the platform. If the boy comes to the centre of the platform, then the new angular velocity becomes ______.
In uniform circular motion, although the speed is constant, why does acceleration occur?
What is the direction of the velocity of an object at any point during uniform circular motion?
What is the direction of the velocity of an object at any point during uniform circular motion?
