Physics Force & Laws Of Motion Level: Misc Level
A projectile of mass 0.902 kg is shot straight up with an initial speed of 16.2 m /s. (a) How high would it go if there were no air resistance? (b) If the projectile rises to a maximum height of only 8.57 m, determine the magnitude of the average force due to air resistance.
Physics Work,Power & Energy Level: Misc Level
A skier starts from rest at the top of a hill. The skier coasts down the hill and up a second hill,as the drawing illustrates. The crest of the second hill is circular, with a radius of 33.4 m. Neglect friction and air resistance. What must be the height h of the first hill so that the skier just loses contact with the snow at the crest of the second hill?
Physics Work,Power & Energy Level: Misc Level
A 0.568 kg basketball is dropped out a window that is 5.72 m above the ground. The ball is caught by a person whose hands are 1.58 m above the ground. (a) How much work is done on the ball by its weight? What is the gravitation potential energy of the basketball, relative to the ground, when it is (b) released and (c) caught? (d)What is the change (P Ef- P E o) in the ball's gravitational potential energy?
Physics Force & Laws Of Motion Level: Misc Level
A 16 - kg sled is being pulled along the horizontal snow -covered ground by a horizontal force of 29 N. Starting from rest, the sled attains a speed of 2.6 m /s in 5.0 m. Find the coefficient of kinetic friction between the runners of the sled and the snow.
Physics Work,Power & Energy Level: Misc Level
A 149 -kg crate is being pulled across a horizontal floor by a force P that makes an angle of 26.7 % above the horizontal. The coefficent of kinetic friction is 0.220. What should be the magnitude of P so that the net work done by it and the kinetic frictional force is zero?
Physics Electrostatics Level: Misc Level
Two small beads having positive charges 24 q and q are fixed at the opposite ends of a horizontal insulating rod, extending from the origin (the location of the larger charge )to the point x =d. As shown in Figure. A third small charged bead is free to slide on the rod. At what position is the third bead in equilibrium?
Physics Properties Of Matter Level: Misc Level
Suppose that 2.00 g of hydrogen is separated into electrons and protons. Suppose also that the protons are placed at the Earth s North Pole and the electrons are placed at the South Pole. What is the resulting compressional force on the Earth?
Chemistry Mole Concept Level: Misc Level
Calculate the number of moles of the positive ions present in 9.71 g of barium phosphide, Ba3 P2
Chemistry Physical Chemistry Level: Misc Level
Calculate the percentage by mass of nitrogen in ammonium perchlorate
Chemistry Mole Concept Level: Misc Level
Calculate the number of molecules in 4.75 millimol of phosphine
Physics Current Electricity Level: Misc Level
An extension cord made of two wires of diameter 0.129 cm (no. 16 copper wire) and of length 2.7 m (9.0 ft) is connected to an electric heater which draws 10.0 A on a 1.2 E 2-V line. How much power is dissipated in the cord?
Physics Current Electricity Level: Misc Level
At $0. 071 per kWh, what does it cost to leave a 1.0 E 2 -W porch light on day and night for a year?
Physics Current Electricity Level: Misc Level
What is the maximum voltage that can be applied across a 7.3 -k? resistor rated at 1 /4 watt?
Enter your answer with 2 significant digits.
Physics Heat & Thermodynamics Level: Misc Level
How much would you have to raise the temperature of a copper wire (originally at 20.0 %C) to increase its resistance by 5.00 percent?
Physics Current Electricity Level: Misc Level
Calculate the ratio of the resistance of 22.0 m of aluminum wire 2.5 mm in diameter, to 16.0 m of copper wire 1.8 mm in diameter.
Enter the ratio as a decimal.
