# 1013 - Physics Questions Answers

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We request you to submit questions of any topic under the same category by selecting topic from the drop down list. Some students are asking question of one topic under the name of another topic. This creates inconvenience.

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Submit By: MANISH SIR 6 year ago
is this topic helpfull: 81 23

A 20 cm long test tube (cylindrical) is inverted & pushed vertically down into the water . when the closed end is at water surface, how high has the water risen inside the tube?  [p atm =10^5 N/m²]

Asked By: AMIT DAS 8 year ago

Let the height of water in the tube is x cm. then according to PV = constant, calculate the pressure by (20-x) cm. column

then P0 + pressure by 20 cm water = pressure by (20-x) cm. column + pressure by x cm water column

A spherical black body with a radius 12 cm radiates 450 w power at 500 k . If the radius were halved and the temperature doubled, the power radiated in watt would be ?
Asked By: ASHISH RANA 8 year agoSolved By: NIKHIL VARSHNEY

A body is moving towards north with initial velocity of 13m/s. Its is subjected to a retardation of 2 m/s2 towards south.The distance travelled in 7th sec is ??

Asked By: NIKHIL VARSHNEY 8 year ago

displacement of any particular sec. = u+at-(a/2)

here direction of motion is opposite to the direction of acceleration so formula will be u-at+(a/2)

displacement in 7th sec = 0

now we know that direction of motion will become south after 6.5 sec. so distance for last half sec = ut+(1/2)at= 1/4

same will be the distance for the first half sec of 7th. so total distance for 7th sec = 1/4 + 1/4 = 1/2