2) ÈËË ma Now, three masses m₁ = 3.5 kg, m₂ = 10.5 kg and m3 = 7 kg hang from three identical springs in a motionless elevator. The springs all have the same spring constant that you just calculated above. What is the force the top spring exerts on the top mass? N Submit

A block whose weight is 40 N rests on a horizontal surface. The coefficient of static friction between the block and the surface is 0.50. A string is attached to the block. The string is pulled horizontally with a force of 15 N. Which one of the following statements is correct? O The magnitude of the force of friction on the block is 20 N. O The magnitude of the force of friction on the block is 15 N. O The force of friction cannot be determined because the coefficient of kinetic friction is not given. O The force of friction cannot be determined because the normal force of the surface on the block is not known. O The magnitude of the force of friction on the block is 5 N.

t The center of mass of the arm shown in the figure is at point A. Find the magnitudes (in N) of the tension force F, and the force F which hold the arm in equilibrium. (Let 8 = 24.0º.) Assume the weight of the arm is 44.7 N. S 0 8.00 cm N e N 29.0 cm. F

Part A Find the magnitude of the force the Sun exerts on Neptune. Assume the mass of the Sun is 2.0x1030 kg, the mass of Neptune is 1.02x1026 kg, and the orbit is 4.50x10° km. Express your answer with the appropriate units. HÀ F = Value Units Submit Request Answer Ne Provide Feedback 4 MacBook F7

A 2.50-kg object is moving in a plane, with its x and y coordinates given by x = 6t² - 2 and y = 5t³ + 1, where x and y are in meters and t is in seconds. Find the magnitude of the net force acting on this object at t = 1.60 s. N

n the figure to the right, the hanging mass m) is 2.50kg. What would be the required mass on the table (M) for the system to move with an acceleration of a=7.25m/s²? part of your solution, you are required to fill out the following: As

A teenager of mass m1 = 56 kg pushes backwards against the ground with his foot as he rides his skateboard. This exerts a horizontal force of magnitude F foot = = 18.5 N. The skateboard has m2 = 2.6 kg. a. Write an expression for the magnitude of the horizontal component of force that the ground exerts on the teenagers foot, F ground. b. Write an expression in terms to given quantities for the magnitude of the skateboard acceleration, a , while the teenager is pushing backwards on the ground? c. What is the numerical value of the magnitude of the acceleration, a, in m/s square?

Å A student tries to push a 27.7 kg desk across the room. She pushes at a downward angle of 39° (measured from the horizontal) with a force of 240 N. As a result, the desk moves with a constant velocity of 1.22 m/s. How much friction is present? F₁ = How much does the desk weigh? 11 N FN = Fg How much Normal force must be present? N N

Two ice skaters, with masses of 36.0 kg and 75.0 kg, are at the center of a 40.0 m diameter circular rink. The skaters push off against each other and glide to opposite edges of the rink. Part A If the heavier skater reaches the edge in 20.0 s , how long does the lighter skater take to reach the edge? ΑΣΦ Submit Request Answer