SMDEP Physics Newton’s Laws, friction, uniform circular motion

New homework policy Only first and last problems are required Others are optional, “bonus points”, good practice New office hours for KR: –WTh 5:30-6:30 PM in Marigold’s

Ch 5, #15(a): minimum coefficient of friction Other 6.Didn’t finish

Ch 5, #15(b): speed of snow before falling off roof m/s 2.32 m/s m/s m/s 5.Other 6.Didn’t finish

Ch 5, #15(c): speed of snow hitting ground 1.15 m/s 2.14 m/s m/s m/s 5.Other 6.Didn’t finish

Ch 5, #24: (a), (b) kg, 3.2 kg kg, 13.4 kg kg, 6.7 kg 4.Other 5.Didn’t finish

Ch 5, #40: minimum speed 1.98 m/s 2.16 m/s m/s m/s 5.Other 6.Didn’t finish

Ch 5, #75: speed 1.28 m/s, 0.44 rev/s m/s, 0.04 rev/s m/s, 12.3 rev/s 4.78 m/s, 1.2 rev/s 5.Other 6.Didn’t finish

Attendance: Which of these do you use most often? 1.Wikipedia 2.Facebook 3.Google 4.Myspace 5.iTunes 6.None

A kid on a skateboard wants to drop a ball into a bucket ahead. Where should the kid be when she releases the ball? After passing the bucket 2.Right above the bucket 3.Before passing the bucket

A box sits on a conveyor belt without slipping. The belt maintains a constant speed to the right. The force of friction on the box is: 1.To the right 2.Zero 3.To the left

Your textbook sits motionless on your flat, horizontal desktop. Is there a force of friction acting on it? 1.Yes 2.No

You push your textbook at constant velocity along your flat, horizontal desktop. Is there a force of friction acting on it? 1.Yes 2.No

Your textbook sits motionless on an inclined surface. Is there a force of friction acting on it? 1.Yes 2.No

An object is held in place by friction on an inclined surface. The angle of inclination is increased until the object starts moving. If the surface is kept at this angle, the object: 1.Slows down. 2.Moves at uniform speed. 3.Speeds up. 4.None of the above.