A fire helicopter carries a 620-kg bucket of water at the end of a 20.0-m-long cable. Flying back from a fire at a constant speed of 40.0 m/s, the cable makes an angle of 40.0° with respect to the vertical. Determine the force exerted by air resistance on the bucket.

A black aluminum glider floats on a film of air above a level aluminum air track. Aluminum feels essentially no force in a magnetic field, and air resistance is negligible. A strong magnet is attached to the top of the glider, forming a total mass of 240 g. A piece of scrap iron attached to one end stop on the track attracts the magnet with a force of 0.823 N when the iron and the magnet are separated by 2.50 cm. (a) Find the accelerationof the glider at this instant. (b) The scrap iron is now attached to another green glider, forming total mass 120 g. Find the acceleration of each glider when the gliders are simultaneously released at 2.50-cm separation.

Many birds can attain very high speeds when diving. Using radar, scientists measured the altitude of a barn swallow in a vertical dive; it dropped 208 m in 3.0 s. The mass of the swallow was estimated to be 0.018 kg, and its cross-section area as 5.6 x 10-4 m2. What was the drag coefficient for this swallow as it dove?

Two crates of fruit  are released from the top of a ramp inclined at 30 degrees from the horizontal and 4.5 meter long. The two crates consist of  an apple crate of mass 20 kg that is placed in front of a watermelon crate of mass 80 kg.  The apple crate has a coefficient of friction of 0.20 while the watermelon crate has a coefficient of friction of 0.15. How long does it take the apple crate to reach the bottom of the incline if it needs to travel a distance of 4.5 meters?

You are pulling your luggage in an air port for an international flight. You know not to pack too much else they charge you extra fees so you weighted your luggage at home to be 22.0 kg. You exert a pull of 46 N in magnitude and at 24 degrees above the horizontal to ensure you can walk at a constant speed on the carpeted floor. What is the coefficient of friction between the caster wheels and the carpet?

Joe pushes down the length of the handle of a 14.1 kg lawn spreader. The handle makes an angle of 47.1° with the horizontal. Joe wishes to accelerate the spreader from rest to 1.39 m/s in 1.7 s. What force must Joe apply to the handle? Answer in units of N.

A roller-coaster car is towed up an incline at a steady speed of 0.500 m/s by a chain parallel to the surface of the incline. The slope is 3.00%, which means that the elevation increases by 3.00 m for every 100.0 m of horizontal distance. The mass of the roller-coaster car is 594 kg. Ignoring friction, what is the magnitude of the force exerted on the car by the chain?

A package of weather instruments is attached to a weather balloon. The package has a mass of 12.4 kg. The system is released vertically from rust. The weather balloon provides a constant lift force of 122.5 N for 6 minutes. calculate the magnitude and direction of the instruments acceleration during the first six minutes of flight ignore air resistance.

You are designing a high-speed elevator for a new skyscraper. The elevator will have a mass limit of 2400 kg (including passengers). For passenger comfort, you choose the maximum ascent speed to be 18.0 m/s, the maximum descent speed to be 10.0 m/s, and the maximum acceleration magnitude to be 5.00 m/s2. Ignore friction. What is the maximum upward force that the supporting cables exert on the elevator car?