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Working with a buoyant force on a balloon.

A balloon is descending with a constant acceleration "a" less than 'g' weight of the balloon with the basket and the contents is W. What weight m of the basket should be released so that the balloon will begin to accelerate upwards with constant acceleration 'a' ? Neglect air resistance.

Physics Net torque: angular acceleration of cylinder caused by descending mass.

See attached file. Mass m= 8 kg is suspended from a cord which passes over a frictionless pulley then wraps tengentially on the surface of a uniform cylinder, mass M= 12 kg radius R = .66 m, on a plane inclined at angle b= 25 degrees from horizontal. As the suspended mass descends it gives angular acceleration A to the cylind

Working with centripetal acceleration and force.

A child is twirling a 0.0120 kg ball on a string in a horizontal circle whose radius is 0.100 m. The ball travels once around the circle in 0.500 s. (a) Determine the centripetal force acting on the ball. (b) If the speed is doubled, does the centripetal force double? If not, by what factor does the centripetal force incre

Coefficient of kinetic friction

During a hockey game, a puck is given an initial speed of 12.00 m/s. It slides 54.00 m on the ice before it stops. What is the coefficient of kinetic friction between the puck and the ice?

True or false questions regarding the acceleration of an elevator.

An object of mass m is hanging by a string from the roof of an elevator. We want to compare the tension in the string to the weight of the object under various conditions. Which statements are true? (Give ALL correct answers) A) If the elevator is moving upwards, but slowing down, the tension in the string is equal to the ob

True and false questions about mass and acceleration.

A small box of mass m is stacked on top of a large box of mass 3m. The interaction between the large box and the horizontal surface on which it slides is frictionless, but the interaction between the two boxes is NOT frictionless. The small box does not slide when a horizontal force F is applied to the large box. Which statement


Shown from the top view are six blocks that are sitting at rest on rotating turntables. All of the turntables have the same rotation rate (i.e. same frequency). The masses of the blocks and how far out from the center they sit varies. The specific values are given in the figures. Which of the following statements are true abo

Working with uniform acceleration and the collision point between two players.

There are two football players standing 48 meters apart (player A and player B). They start running towards each other. Player A acceleration is 0.5 m/s2 and player B acceleration is 0.3 m/s2. How much time passes before each player collides with each other? When they collide how far has the first player(player A) trave

Working with circular motion and centripetal acceleration.

There is a hand held device with a rod with a cord attached to a spring scale on the rod. You swing the ball around in a horizontal circle with a radius of 0.500 m. There are several parts to this that I need help with. If the speed of the ball is 3.7 m/s, how do you calculate the expected tension in the cord? Why can't you s