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Constant acceleration

"A runner hopes to complete the 10,000-m run in less than 30.0 minutes. After exactly 27.0 minutes, there are still 1100 m to go. The runner must then accelerate at 0.20 m/s^2 for how many seconds in order to achieve the desired time?" Here's what I've done: So far, the runner has gone 8900 m in 1620 s, which should give h

Simple conversion

"A sprinter accelerates from rest to 10.0 m/s in 1.35 seconds. What is her acceleration in (a) m/s^2, and (b) km/h^2?" I got (a) right. Acceleration = 10/1.35 = 7.41 m/s^2. But I somehow screw it up when I go to do the conversion. Here's what I did: 10 m = 0.01 km 1.35 s = 3.75 x 10^-4 hr (1.35 x (1 hr/3600 s) So the s

Force, acceleration, coefficient of kinetic friction

See attached file for the graph. In the figure below, m1 = 10.7 kg and m2 = 4.15 kg. The coefficient of kinetic friction is 0.271. If the system is set in motion with m2 moving downward, what will be the acceleration of the system? I'm not sure how to factor in the coefficient of kinetic friction. Can you show me how to do

Vectors and distance: How far in advance must rescue aircraft drop supplies

See attached drawing in Word file. Please give me a step by step rundown of how to do it? "A rescue plane wants to drop supplies to isolated mountain climbers on a rocky ridge H = 227 m below. If the plane is traveling horizontally with a speed of 223 km/hr (61.9 m/s), how far in advance of the recipients (horizontal dista

Average acceleration

Hi. Here's my problem: "A tennis ball with a speed of 11.8 m/s is thrown perpendicularly at a wall. After striking the wall, the ball rebounds in the opposite direction with a speed of 8.51 m/s. If the ball is in contact with the wall for 0.00175 s, what is the average acceleration of the ball while it is in contact with the

Force applied to an object of mass produces acceleration; what is the value?

Please help with the following problem. A force F applied to an object of mass m1 produces an acceleration of 3.00m/s^2. The same force applied to a second object of mass m2 produces an acceleration of 1.00m/s^2. (a) What is the value of m1/m2?.........I understand that a2/a1=1/3 --answer (b) If m1 and m2 were combine

Newton's Laws: Wedge and block mass, magnitude, acceleration

A.) A wedge with mass M rests on a frictionless horizontal tabletop. A block with mass m is placed on the wedge. There is no friction between the block and the wedge. The system is released from rest. Calculate: i) the acceleration of the wedge ii) the horizontal and vertical components of the acceleration of the block.

Physics Problems ( Motion )

View attachment I would like detail easy to understand answers , and if u need a drawing ( figure ) for the problem email me , i will email you back if i have a drawing. Thank you

A person and cage are suspended from pulley; Find force exerted on rope

A man sitting in a cage is connected to a pulley system of three movable and one fixed pulley in the system shown in ATTACHMENT #1. He pulls down on a rope as shown, to raise himself and the cage. The man and cage have a total weight of 639 nt. Ignore friction as negligible. PART a. Find the force he exerts to move upward

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