Question A particle is moving in a circle of diameter 20m. What is its distance and as per the table given below

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Beverly Leonard
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1 A train accelerates from 36 km/h to 54 km/h in 10 sec. (i) Acceleration (ii) The distance travelled by car. As it comes down to the initial point Net displacement is zero Net distance=200 m A body whose speed is constant (a) Must be accelerated (b) Might be accelerated (c) Has a constant velocity (d) Cannot be accelerated. might be accelerated A truck traveling at 54 km/h is slow down to 36 km/h in 10 sec. Find the retardation Acceleration is given by a=δvδt So a=-.5 m/s 2 Negative sign implies retardation A particle is moving in a circle of diameter 20m. What is its distance and as per the table given below S.no Rounds Displacement Distance S.no Rounds Displacement Distance π m 30π π m 50π A train starts from rest and accelerate uniformly at the rate of 5 m/s2 for 5 sec. Calculate the velocity of train in 5 sec. 25m/s

2 A object moves with uniform positive acceleration. Its velocity-time graph will be (a) A straight line parallel to the time axis (b) A straight line inclined at an obtuse angle to the time axis (c) A straight line inclined at an acute angle to the time axis (d) None of these. is (c). A object goes from point X to Y and then come back from Y to X. What is the displacement and average velocity? Displacement is zero as it come back to it initial point. Now Average velocity is given Displacement/time. Since displacement is zero, Average velocity is also zero. Write down the difference between Scalars and Vectors? S.No Scalars Vectors 1 It has magnitude only It has magnitude and direction both 2 Example are speed,time,mass,charge Example are velocity,displacement,acceleration,force. Four Cyclist A,B,C,D starts at the same point and at the same time and move in a straight line to reach destination.they all move with uniform velocities. They reach the destination in the following order C A B D the following questions a. If the displacement-time graph is plotted for each cyclist, which will be having highest slope b. Arrange the cyclist in decreasing order of velocity Since C is fastest cyclist, it velocity is highest and Slope of displacement time graph will be highest for him Velocity of cyclist in decreasing order C>A>B>D. What do you infer if? Distance time graph is straight line 2 Velocity time graph is curved 3 Displacement time is zig zag Distance time graph is straight line Speed is constant 2. Velocity time graph is curved Acceleration is not uniform 3 Displacement time is zig zag Non uniform velocity

3 . What is the difference between Uniform Accelerated and Non Uniform accelerated motion? S.No Uniformly accelerated A body is said to be in uniform acceleration if it travels in a straight line and its velocity increases or decreases by equal amounts in equal intervals of time. Motion under acceleration under gravity is perfect example for uniform accelerated motion Following equations could be use here v2=u2+2as v=u+at s=ut+12at2 Non uniformly accelerated A body is said to be in non uniform acceleration if the rate of change of its velocity is not constant in equal intervals of time A car moving in a straight line. Some time putting more pressure on the accelerator pedal is a perfect example of non uniform accelerated motion. No equation available. What happens to speed, velocity acceleration when an object moves in a circle with uniform speed? Speed remains constant Velocity magnitude remains constant, but direction changes continuously Acceleration magnitude remains constant but direction changes continuously. When an object is thrown upwards, what is true of velocity and acceleration at the highest point of motion of the object? Velocity becomes zero Acceleration remains same as g. True and False Statements A) Displacement can be zero but distance never B) Displacement magnitude can be greater than distance travelled by the object C) Time is a vector quantity D) If the velocity of the body decreases with time, the acceleration is negative (retardation), and the motion is called decelerated motion E) The area of the velocity time graph gives displacement of the body F) Acceleration is a scalar quantity G) Motion and rest are relative terms I) an object can be moving with Uniform speed but variable acceleration A) True B) True C) False D) True E) True F) False G) True I) True

4 . Gave the formula for each 1 Relation between Initial, final velocity,acceleration and displacement in a uniformly accelerated straight line motion 2 Average velocity 3 Relation between Initial, final velocity,acceleration and time in a uniformly accelerated straight line motion 4 Relation between Initial velocity,acceleration,displacement and time in a uniformly accelerated straight line motion 5 Average acceleration 6 Average speed 1 Relation between Initial, final velocity,acceleration and displacement in a uniformly accelerated straight line motion v2=u2+2as 2 Average velocity v=dt 3 Relation between Initial, final velocity,acceleration and time in a uniformly accelerated straight line motion v=u+at 4 Relation between Initial velocity,acceleration,displacement and time in a uniformly accelerated straight line motion s=ut+12at2 5 Average acceleration a=δvt 6 Average speed s=dt An airplane accelerates down a runway at 3.20 m/s 2 for 32.8 s until is finally lifts off the ground. Determine the distance traveled before takeoff. distance= 1720 m A Jeep starts from rest and accelerates uniformly over a time of 5.21 seconds for a distance of Jeep. 110m. Determine the acceleration of the acceleration = 8.10 m/s 2 John is riding the Giant Drop at Canada. If John free falls for 2.6 seconds, what will be his final velocity and how far will he fall? Velocity = m/s (-indicates direction) A race car accelerates uniformly from 18.5 m/s to 46.1 m/s in 2.47 seconds. Determine the acceleration of the car and the distance traveled. acceleration = 11.2 m/s 2, d= 79.8 m

5 A feather is dropped on the planet other than earth which has very low acceleration due to gravity from a height of 1.40 meters. The acceleration of gravity on the other planet is 1.67 m/s 2. Determine the time of feather to fall to the surface of the other planet time= 1.29 s Rocket-powered sleds are used to test the human response to acceleration. If a rocket- powered sled is accelerated to a speed of 444 m/s in 1.8 seconds, then what is the acceleration and what is the distance that the sled travels? acceleration = 247m/s 2 Honda Activita accelerates uniformly from rest to a speed of 7.10 m/s over a distance of 35.4 m. Determine the acceleration of the bike. acceleration = m/s 2 An Aeronautics engineer is designing the runway for an airport. Of the planes that will use the airport, the lowest acceleration rate is likely to be 3 m/s 2. The takeoff speed for this plane will be 65 m/s. Assuming this minimum acceleration, what is the minimum allowed length for the runway? distance= 704m A BMW car travelling at 22.4 m/s skids to a stop in 2.55 s. Determine the skidding distance of the car (assume uniform acceleration) distance= 28.6m A kangaroo is capable of jumping to a height of 2.62 m. Determine the takeoff speed of the kangaroo. speed= 7.17m/s If Rahul has a vertical leap of 1.29 m, then what is his takeoff speed and his hang time (total time to move upwards to the peak and then return to the ground)? speed= 5.03m/s, hang time = 1.03s A bullet leaves a rifle with a muzzle velocity of 521m/s. While accelerating through the barrel of the riffle, the bullet moves a distance of m. Determine the acceleration of the bullet (assume a uniform acceleration). acceleration = m/s 2

6 A baseball is popped straight up into the air and has a hang- time of 6.25 s. Determine the height to which the ball rises before it reaches its peak. (Hint: the time to rise to the peak is one- half the total hang-time.) speed=30.6m/s, d= 47.9m The observation deck of the tall skyscraper 370 m above the street. Determine the time required for a penny to free fall from the deck to the street below. time= 8.69s A bullet is moving at a speed of 367 m/s when it embeds into a lump of moist clay. The bullet penetrates for a distance of m. Determine the acceleration of the bullet while moving into the clay. (assume a uniform acceleration.) acceleration = m/s 2 (Negative sign shows deceleration) A coin is dropped into a deep well and is heard to hit the water 3.41 s after being dropped. Determine the depth of the well. distance= 57.0m It was once recorded that a Jaguar left skid marks that were 290 m in length. Assuming that the Jaguar skidded to a stop with a constant acceleration of m/s 2, determine the speed of the Jaguar before it began to skid. speed= 47.6m/s A plane has a takeoff speed of 88.3 m/s and requires 1365 m to reach that speed. Determine the acceleration of the plane and the time required to reach this speed. acceleration = 2.86m/s 2 A dragster accelerates to a speed of 112 m/s over a distance of 398 m. Determine the acceleration (Assume uniform) of the dragster. time= 30.8s, acceleration = 15.8m/s 2 With what speed in miles/ h (1 m/s= 2.23 mi/hr) must an object be field)? Assume negligible air resistance. thrown to reach a height of 91.5 m (equivalent to one football vi= 42.3m/s

Kinematic Equations. t! +! 1 2 at 2!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!v f 2 =!v i 2 +!2ad. !!!!!!!!!!!!!!d! =!v i. !!!!!!!!!!!!!!!!

Kinematic Equations. t! +! 1 2 at 2!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!v f 2 =!v i 2 +!2ad. !!!!!!!!!!!!!!d! =!v i. !!!!!!!!!!!!!!!! Kinematic Equations Objectives: Students will use kinematic equations to describe and represent the motion of objects by determining: the distance traveled by an object with constant acceleration. the