A small coin is placed on a record rotating at `33 1/3` rev/minute. The coin does not slip on the record. Where does it get the required centripetal force from?

As mosquito is sitting on an L.P. record disc rotating on a trun tabel at 33 1/3 revolutions per minute. The distance of the mosquito from the centre of the turn table is 10 cm. Show that the friction coefficient between the record and the mosquito is greater than pi^2/81 . Take g=10m/s^2

A classroom demonstration of Newton's first law is as follows: A glass is covered with a plastic card and a coin is placed on the card. The card is given a quick strike and the coin falls in the glass. a.Should the friction coefficient between the card and the coin be small or large? b. Should the coin be light or heavy? c. Why does the experiment fail if the card is gently pushed?

A coin placed on a rotating turntable just slips if it is placed at a distance of 4 cm from the centre. If the angular velocity of the turntable is doubled, it will just slip at a distance of

A box contains N coins m of which are fair and the rest are biased. The probability of getting a head when a fair coin is tossed is 1/2, while it is 2/3 when a biased coin is tossed. A coin is drawn from the box at random and is tossed twice. The first time it shows head and the second time it shows tail. What is the probability that the coin drawn is fair?

In a game a coin is tossed 2n+m times and a player wins if he does not get any two consecutive outcomes same for at least 2n times in a row. The probability that player wins the game is a. (m+2)/(2^(2n)+1) b. (2n+2)/(2^(2n)) c. (2n+2)/(2^(2n+1)) d. (m+2)/(2^(2n))

Read the paragraph and answer the following question: You must be knowing about the high and low tides that occur regularly in the sea. The level of the sea water at any given location along sea shore increases and decreases twice a day at regular intervals. High and low tides occur at different times at places. The level of water in sea changes because of the gravitational force exerted by the moon. Water directly under the moon gets pulled towards the moon and the level of water there goes up causing high tide at that place. At two places on the earth at 90^(@) from the place of high tide, the level of water is minimum and low tides occur there. How does sea level changed?

A circular coil of radius 8.0 cm and 20 turns is rotated about its vertical diameter with an angular speed of 50 rad s^(-1) in a uniform horizontal magnetic field of magnitude 3.0xx10^(-2)T . Obtain the maximum and average emf induced in the coil. If the coil forms a closed loop of resistance 10Omega , calculate teh maximum value of current in the coil Calculated the average power loss due to Joule heating. Where does this power come from?

The volume of a sphere is given by V= 4/3 pi R^3 where R is the radius of the sphere (a). Find the rate of change of volume with respect to R. (b). Find the change in volume of the sphere as the radius is increased from 20.0 cm to 20.1 cm. Assume that the rate does not appreciably change between R=20.0 cm to R=20.1 cm.