SEMESTER 2 CHAPTER 1 CIRCULAR MOTION

CHAPTER -1 CIRCULAR MOTION














Image result for banked car racing tracks
http://www.animations.physics.unsw.edu.au/jw/circular.htm#acceleration





Angular displacement

The angular displacement is defined as the angle through which an object moves on a circular path. It is the angle, in radians, between the initial and final positions. (θf - θi) = angular displacement.
 θ = s/r. 
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QUESTION 1

QUESTION 2


QUESTION 3

QUESTION 4
QUESTION 5








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http://hyperphysics.phy-astr.gsu.edu/hbase/cf.html

Application questions
1.A car when it takes a turn skids off the road if there is oil spillage on the road.Why?

2.Race tracks are banked (outer edge of road raised over the inner edge) at curves .Explain.
 enter image description here
Image result for banked roads physics
3.How does a centrifuge work?

It is a device which is used to spin objets at high speed about an axis.It is used to seperate particles in mixture.More massive particles require more centripetal force than lighter particles in order to maintain circular motion.As a result more massive particles seperates from lighter ones.
Image result for centrifuge 


 

http://www.physicsclassroom.com/calcpad/circgrav/problem 

Which are the forces acting on the  body?


Write the equation for centripetal force


Question 11. A 2 kg ball on a string is rotated about a circle of radius 10 m. The maximum tension allowed in the string is 50 N. What is the maximum speed of the ball? 




Problem :12
During the course of a turn, an automobile doubles its speed. How much additional frictional force must the tires provide if the car safely makes around the curve? 





Problem :13
A satellite is said to be in geosynchronous orbit if it rotates around the earth once every day. For the earth, all satellites in geosynchronous orbit must rotate at a distance of 4.23×107 meters from the earth's center. What is the magnitude of the acceleration felt by a geosynchronous satellite? 









Solution: The acceleration felt by any object in uniform circular motion is given by a = . We are given the radius but must find the velocity of the satellite. We know that in one day, or 86400 seconds, the satellite travels around the earth once. Thus:Time period T of satellite=86400s
Angular speed   w=2  × π / T  =2x3.14/86400

But v = rw
v=4.23x 107  x  2x3.14/86400  = 3076
thus

a = = = .224 m/s2




Problem :14
A popular daredevil trick is to complete a vertical loop on a motorcycle. This trick is dangerous, however, because if the motorcycle does not travel with enough speed, the rider falls off the track before reaching the top of the loop. What is the minimum speed necessary for a rider to successfully go around a vertical loop of 10 meters? 










solution
During the entire trip, the rider experiences two different forces: the normal force from the track, and the gravitational force. At the top of the loop, both these forces point down, or towards the center of the loop. Thus the combination of these forces provides the centripetal force at that point. At the minimum speed of the motorcycle, however, he experiences no normal force. One can see this by envisioning that if the rider had gone any slower, he would have fallen off the track. Thus, at the minimum speed, all the centripetal force is provided by gravity. Plugging into our equation for centripetal force, we see that

mg =
Rearranging the equation,
v min = = = 9.9 m/s
Thus the rider must be traveling at least 9.9 m/s to make it 
Q 15 ) What is the angular velocity of the second hand and minute hand of the clock?





Q16 )  What is the value of the angular velocity of a point on the surface of the Earth?


























Q17)Calculate the angular velocity, in rad/s, corresponding to 20 revolutions per minute.

















Q18)A 2 kg ball on a string is rotated about a circle of radius 10 m. The maximum tension allowed in the string is 25 N. What is the maximum speed of the ball? 





















19)A child of mass 20 kg sits on the roundabout without holding the bars.

The distance from the centre of the roundabout to the centre of gravity of the child is 0.80 m. The maximum frictional force between the roundabout and the child is 0.35 × the weight of the child. Calculate the minimum time taken for one revolution of the roundabout if the child is not to slide off




 







































 







A body of mass 0.4 kg is whirled in a horizontal circle of radius 2 m with a constant speed of 10 ms . Calculate its (i) angular speed (ii) frequency of revolution (iii) time period and (iv) centripetal acceleration.

Read more at: http://www.askphysics.com/numerical-problems-from-uniform-circular-motion-online-home-work-for-kv-pattom-class-11-students/

What is the angular velocity of a second hand and minute hand of a cloc

Read more at: http://www.askphysics.com/numerical-problems-from-uniform-circular-motion-online-home-work-for-kv-pattom-class-11-students/
What is the angular velocity of a second hand and minute hand of a clock? A body of mass 0.4 kg is whirled in a horizontal circle of radius 2 m with a constant speed of 10 ms . Calculate its (i) angular speed (ii) frequency of revolution (iii) time period and (iv) centripetal acceleration. A circular wheel of 0.50 m radius is moving with a speed of10 ms. Find the angular speed. Assuming that the moon completes one revolution in a circular orbit around the earth in 27.3 days, calculate the acceleration of the moon towards the earth. The radius of the circular orbit can betaken as 3.85 x 10 km. The angular velocity of a particle moving along a circle of radius 560 cm is increased in 5 minutes from 100 revolutions per minute to 400 revolutions per minute. Find Light bulb angular acceleration and (ii) linear acceleration. Calculate the linear acceleration of a particle moving in a circle of radius 0.4 m at the instant when its angular velocity is 2 rad /s and its angular acceleration is 5 rad/s2 A threaded rod with 12 turns per cm and diameter 1.18 cm is mounted horizontally. A bar with a threaded hole to match the rod is screwed onto the rod. The bar spins at the rate of 216 rpm. How long will it take for the bar to move 1.50 cm along the rod.

Read more at: http://www.askphysics.com/numerical-problems-from-uniform-circular-motion-online-home-work-for-kv-pattom-class-11-students/
What is the angular velocity of a second hand and minute hand of a clock? A body of mass 0.4 kg is whirled in a horizontal circle of radius 2 m with a constant speed of 10 ms . Calculate its (i) angular speed (ii) frequency of revolution (iii) time period and (iv) centripetal acceleration. A circular wheel of 0.50 m radius is moving with a speed of10 ms. Find the angular speed. Assuming that the moon completes one revolution in a circular orbit around the earth in 27.3 days, calculate the acceleration of the moon towards the earth. The radius of the circular orbit can betaken as 3.85 x 10 km. The angular velocity of a particle moving along a circle of radius 560 cm is increased in 5 minutes from 100 revolutions per minute to 400 revolutions per minute. Find Light bulb angular acceleration and (ii) linear acceleration. Calculate the linear acceleration of a particle moving in a circle of radius 0.4 m at the instant when its angular velocity is 2 rad /s and its angular acceleration is 5 rad/s2 A threaded rod with 12 turns per cm and diameter 1.18 cm is mounted horizontally. A bar with a threaded hole to match the rod is screwed onto the rod. The bar spins at the rate of 216 rpm. How long will it take for the bar to move 1.50 cm along the rod. You may also like:

Read more at: http://www.askphysics.com/numerical-problems-from-uniform-circular-motion-online-home-work-for-kv-pattom-class-11-students/
What is the angular velocity of a second hand and minute hand of a clock? A body of mass 0.4 kg is whirled in a horizontal circle of radius 2 m with a constant speed of 10 ms . Calculate its (i) angular speed (ii) frequency of revolution (iii) time period and (iv) centripetal acceleration. A circular wheel of 0.50 m radius is moving with a speed of10 ms. Find the angular speed. Assuming that the moon completes one revolution in a circular orbit around the earth in 27.3 days, calculate the acceleration of the moon towards the earth. The radius of the circular orbit can betaken as 3.85 x 10 km. The angular velocity of a particle moving along a circle of radius 560 cm is increased in 5 minutes from 100 revolutions per minute to 400 revolutions per minute. Find Light bulb angular acceleration and (ii) linear acceleration. Calculate the linear acceleration of a particle moving in a circle of radius 0.4 m at the instant when its angular velocity is 2 rad /s and its angular acceleration is 5 rad/s2 A threaded rod with 12 turns per cm and diameter 1.18 cm is mounted horizontally. A bar with a threaded hole to match the rod is screwed onto the rod. The bar spins at the rate of 216 rpm. How long will it take for the bar to move 1.50 cm along the rod. You may also like:

Read more at: http://www.askphysics.com/numerical-problems-from-uniform-circular-motion-online-home-work-for-kv-pattom-class-11-students/
All students of class XI are to copy down the questions and solve it in the home work copy and solve it to submit on or before 22 Sept 2014. What is the angular velocity of a second hand and minute hand of a clock? A body of mass 0.4 kg is whirled in a horizontal circle of radius 2 m with a constant speed of 10 ms . Calculate its (i) angular speed (ii) frequency of revolution (iii) time period and (iv) centripetal acceleration. A circular wheel of 0.50 m radius is moving with a speed of10 ms. Find the angular speed. Assuming that the moon completes one revolution in a circular orbit around the earth in 27.3 days, calculate the acceleration of the moon towards the earth. The radius of the circular orbit can betaken as 3.85 x 10 km. The angular velocity of a particle moving along a circle of radius 560 cm is increased in 5 minutes from 100 revolutions per minute to 400 revolutions per minute. Find Light bulb angular acceleration and (ii) linear acceleration. Calculate the linear acceleration of a particle moving in a circle of radius 0.4 m at the instant when its angular velocity is 2 rad /s and its angular acceleration is 5 rad/s2 A threaded rod with 12 turns per cm and diameter 1.18 cm is mounted horizontally. A bar with a threaded hole to match the rod is screwed onto the rod. The bar spins at the rate of 216 rpm. How long will it take for the bar to move 1.50 cm along the rod. You may also like:

Read more at: http://www.askphysics.com/numerical-problems-from-uniform-circular-motion-online-home-work-for-kv-pattom-class-11-students/
All students of class XI are to copy down the questions and solve it in the home work copy and solve it to submit on or before 22 Sept 2014. What is the angular velocity of a second hand and minute hand of a clock? A body of mass 0.4 kg is whirled in a horizontal circle of radius 2 m with a constant speed of 10 ms . Calculate its (i) angular speed (ii) frequency of revolution (iii) time period and (iv) centripetal acceleration. A circular wheel of 0.50 m radius is moving with a speed of10 ms. Find the angular speed. Assuming that the moon completes one revolution in a circular orbit around the earth in 27.3 days, calculate the acceleration of the moon towards the earth. The radius of the circular orbit can betaken as 3.85 x 10 km. The angular velocity of a particle moving along a circle of radius 560 cm is increased in 5 minutes from 100 revolutions per minute to 400 revolutions per minute. Find Light bulb angular acceleration and (ii) linear acceleration. Calculate the linear acceleration of a particle moving in a circle of radius 0.4 m at the instant when its angular velocity is 2 rad /s and its angular acceleration is 5 rad/s2 A threaded rod with 12 turns per cm and diameter 1.18 cm is mounted horizontally. A bar with a threaded hole to match the rod is screwed onto the rod. The bar spins at the rate of 216 rpm. How long will it take for the bar to move 1.50 cm along the rod. You may also like:

Read more at: http://www.askphysics.com/numerical-problems-from-uniform-circular-motion-online-home-work-for-kv-pattom-class-11-students/

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