1) 1） Express the given angle, 135° in radian. Given as numerical value and as a fraction of π。 a) 0.25π b) 0.75π c) 0.50π d) 0.33π 2) 2） If a disc 30cm in diameter rolls 65m along a straight line without slipping, calculate the number of revolutions would it makes in the process. a) 70rev b) 68rev c) 71rev d) 69rev 3) During a certain period of time, the angular displacement of a swinging door is described by, θ=5.00+10.0t+2.00t², where θ is in radians and t is in seconds. Determine the angular speed at time, t =3.00s.  a) 17.67rads-1 b) 19.5rads-1 c) 22rads-1 d) 20.5rads-1 4) A car is travelling with a velocity of 17.0m s⁻¹ on a straight horizontal highway. The wheels of the car have a radius of 48.0cm. If the car then speeds up with an acceleration of 2.00m s⁻² for 5.00 s, calculate the number of revolutions of the wheels during this period. a) 36.5rev b) 35rev c) 37.5rev d) 36rev 5) The wheels of a bicycle make 30 revolutions as the bicycle reduces its speed uniformly form 50.0 km h⁻¹ to 35.0 km h⁻¹.The wheels have a diameter of 70cm. Calculate the angular acceleration. a) 2.33rads-2 b) -2.13rads-2 c) 2.13rads-2 d) -2.33rads-2 6) A rigid body rotates about a fixed axis through a point in the body, with uniform angular velocity of 600 r.p.m.The velocity then decreases at a constant retardation to 300 r.p.m in 6.0 s.Determine the number of revolutions the body has turned through in the 6.0 s a) 46rev b) 47rev c) 44rev d) 45rev 7) A 5.0N force F is applied to a bar that can pivot around its center as shown in the figure.The force is perpendicular to the bar and is r=0.40m away from the center. What is the torque on the bar? a) 0Nm b) 5.0Nm c) -2.0Nm d) 2.0Nm 8) A 2.0 N force F is applied to a bar that can pivot around its end as shown in the figure.The force is parallel to the bar and is r= 0.50m away from the end. What is the torque on the bar? a) 1.0Nm b) -1.0Nm c) 0Nm d) 2.0Nm 9) Express the following angles in radian: 445。. Give as numerical values and as a fraction of π. a) 2.47π rad b) 2.50π rad c) 0.33 π rad d) 3.00 π rad 10) Calculate the angular velocity of the minute hand of a clock. State in rad s-1. What is the angular acceleration in each case? a) 1.45 x 10-4 rads-1 b) 0.11 rads-1 c) 1.74 x 10-3rads-1 d) 0 rads-1 11) A blade of a ceiling fan has a radius of 0.400m is rotating about a axis with an initial angular velocity of 0.150 rev s-1.The angular acceleration of the blade is 0.750 rev s-2. Determine the angular velocity after 4.00s. a) 1.50π rads-1 b) 19.8rads-1 c) 41.5 rads-1 d) 23 rads-1 12) Figure shows a 3m rod being exerted by 40N force. Calculate the total torque at point A.  a) 120Nm b) 50.0Nm c) 30Nm d) 41.04Nm 13) Figure shows a 8m rod being exerted by 50 N force. Calculate the total torque at point A. a) 259.81Nm b) 80Nm c) 300Nm d) 149.3Nm 14) A solid cylinder of radius 18.0cm is free to rotate about a smooth horizontal axle. A mass of 0.38kg hangs from a string wound around the cylinder as shown in figure above. When the system released from rest, the mass take 2.0s to fall through a height of 5.0m. What is the moment of inertia of the cylinder ?   a) 1.50 x 10-2 kgm2 b) 3.60 x 10-2 kgm2 c) 4.00 x 10-2 kgm2 d) 2.60 x 10-2 kgm2 15) An object of mass is 1.50kg is suspended from a rough pulley of radius 20.0cm by light string as shown in Figure. The pulley has a moment of inertia 0.02kgm2 about the axis of the pulley. The object is released from rest and the pulley rotates without encountering frictional force. Assume that the string does not slip on the pulley. After 0.3s, determine the linear acceleration of the object.  a) 36.8 ms-2 b) 2.21ms-1 c) 7.36 ms-2 d) 0.331 ms-2 16) Figure above shows a weightless rod AB of length 4m. A 30N force is exerted at point B. Calculate the total torque at point A. a) 90Nm b) 60Nm c) 120Nm d) 0Nm

Chapter 8

av
Skriv ut
Bädda in

Rankningslista

Visuell stil

Alternativ

Växla mall

Återställ sparas automatiskt: ?