Problem
Problem I: A ball of mass m = 2 kg is spinning around at a speed of 5 m/s and at a radius of r = 1.2 m. Find the centripetal force acting on the ball.
Problem II: You pull a spring with a force F = 1 N, and stretch it 2 cm. What is the spring constant (k) in units of N/m?
Problem III: You pull up a pail of water from a well at a constant speed with a force of Fyou = 200 N by the use of a pulley as shown on the figure. The pulley is held up by a fixture. The weight of the cord attached to the pail is neglected. What is the net force (Fp) on the pulley by the the fixture? You will want to draw a free body diagram of the pulley in this problem.
Problem IV: A pail of water hangs from a line right in the middle. The line is attached to two poles as shown in the diagram. The weight of the pail is W = 200 N, and the line sags by an angle of θ = 1.2 ? . (i) Draw a free body diagram of the bucket. (ii) Write down the equations one gets from Newton's second law. (iii) Find the tension (T) on the line.
Problem V: Two masses are attached by a string. One of the masses slides on a frictionless table while the other one hangs from a pulley. Such a system is shown in the figure below. The masses are M1 = 350 g and M2 = 250 g. Find the acceleration of each mass (a =?). Again, do not forget to draw the free body diagrams as well as the necessary equations (from Newton's second law) describing the two masses.
Problem VI: You push a block on the pavement with a force of F = 86 N. The block has a mass of M = 10 kg, and the coefficient of kinetic friction between the block and the pavement is µk = 0.26. What is the acceleration (a) of the block?
Problem VII: A block of mass m = 1 kg is placed on a horizontal surface. You start tilting the surface. When the surface makes an angle of θ = 45? with the horizontal, the mass slides down the surface. What is the coefficient of static friction (µs)?
Problem VIII: In this problem you will do problem 5 again but the table will exert a friction force. Suppose that the coefficient of friction between the table and the block is µk = 0.2. Find the acceleration of the two blocks (a =?) and find the tension of the string (T =?)