Human growth and development
Sponges, condoms, birth control, abstinence.
Physics
Consider a skateboarder who starts from rest at the top of a 14.6 m-long ramp that is inclined at an angle of 13.0° to the horizontal. Assuming that the skateboarder's acceleration is g sin 13.0°, find his speed when he reaches the bottom of the ramp in 3.13 s.
physics
Starting from rest, a ball of mass 5 kg experiences a constant force of 40 N for 12 s. What is the final kinetic energy (in J) of the ball after 12 s?
physics
A 64.9 kg skier coasts up a snow-covered hill that makes an angle of 25.4° with the horizontal. The initial speed of the skier is 8.67 m/s. After coasting a distance of 1.92 m up the slope, the speed of the skier is 4.33 m/s. Calculate the work done by the kinetic friction...
physics
A 0.620 kg basketball is dropped out of a window that is 6.40 m above the ground. The ball is caught by a person whose hands are 1.61 m above the ground. How much work is done on the ball by its weight?
physics
Forces of 20 N at 80 degrees, and 50 N at an angle of 210 degrees, measured counter-clockwise from the positive x-axis, act on an object. What are the components (Fx, Fy) of the resultant force (in Newtons)?
physics
A jogger travels a route that has two parts. The first is a displacement A of 2.30 km due south, and the second involves a displacement B that points due east. The resultant displacement A + B has a magnitude of 3.63 km. What is the magnitude of B?
physics
Three deer, A, B, and C, are grazing in a field. Deer B is located 61.1 m from deer A at an angle of 50.9° north of west. Deer C is located 78.4° north of east relative to deer A. The distance between deer B and C is 92.2 m. What is the distance between deer A and C?
physics
A 64.9 kg skier coasts up a snow-covered hill that makes an angle of 25.4° with the horizontal. The initial speed of the skier is 8.67 m/s. After coasting a distance of 1.92 m up the slope, the speed of the skier is 4.33 m/s. Calculate the work done by the kinetic friction...
physics
A 4.92E+2 kg hot-air balloon takes off from rest at the surface of the earth. The nonconservative wind and lift forces take the balloon up, doing +9.81E+4 J of work on the balloon in the process. At what height above the surface of the earth does the balloon have a speed of 7....
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