Physics Heat & Thermodynamics Level: Misc Level
2 objects are added to a container holding 200 g of 20 deg C ethanol. The hot object has a mass of 100 g and is removed from a pot of 212 deg F water, its specific heat being 1 /5 that of water.The other object is taken from a 263 K freezer, Its mass is 75 g and its specific heat heat 30 % that of water. What will be the final equilibrium temperature of the mixture?
Physics Heat & Thermodynamics Level: Misc Level
Surface area of a city is 45 square miles with a snow density of 15% that of water . Average depth of snow is 13 inches. What is the volume in cubic meters of snow covering the city?How much energy in both joules and kcal would be needed to turn this snow (32 deg F) into water? Assume 9 hours of sunlight and average sunlight intensity is 400 W/meter squared. Also assume that 50% of this energy is absorbed by the snow. How many hours of sunlight is needed to melt the snow?
Physics Heat & Thermodynamics Level: Misc Level
Well insulated wall temperature of room A is 20 deg Celsius, and poorly insulated wall temperature of room B is 12 deg Celsius. Body surface temperature is 29 deg Celsius with a surface area of 1.8 meters squared and emissivity of 0.9 what is the man's radiant loss in each house?
Physics Kinematics Level: Misc Level
A ship maneuvers to within 2.50 x 10 ^3 m of an island s 1.80 x10 ^3 mountain peak and fires a projectile at an enemy ship 6.10 x10 ^2 m on the other side of the peak, as illustrated below. If the ship shoots the projectile with an initial velocity of 2.50 x10 ^2 m /s at an angle of 75.0, how close to the enemy ship does the projectile land? How close ( vertically ) does the projectile come to the peak?
Physics Kinematics Level: Misc Level
A place kicker must kick a football from a point 36.0 m (about 40.0 yd) from the goal. As a result of the kick, teh ball must clear the crossbar, which is 3.05 m high. When kicked, the ball leaves the ground with a speed of 20.0 m /s at an angle of 53 to the horizontal. A)by how much does the ball clear or fall short of clearing the crossbar? B) Does the ball approach the crossbar while still rising or while falling?
Physics Kinematics Level: Misc Level
The fastest recorded pitch in baseball was thrown by Nolan Ryan in 1974. If this pitch were thrown horizontally, the ball would fall 0.809 m (2.65 ft) by the time it reached home plate, 18.3 m(60ft) away. How fast was Ryan s pitch?
Physics Work,Power & Energy Level: Misc Level
A 0.60 -kg particle has a speed of 2.0 m/s at point A and a kinetic energy of 7.5 Joules at point B.What is
a. its kinetic energy at A
b.its speed at point B
c.the total work done on the particle as it moves from A to B
Physics Force & Laws Of Motion Level: Misc Level
A box of books weighing 300 N is shoved across the floor of an apartment by a force of 400 N exerted downward at an angle of 35.2 below the horizontal. If the coefficient of kinetic friction between box and floor is 0.570, how long does it take to move the box 400 m, starting from rest?
Physics Work,Power & Energy Level: Misc Level
A block of mass 2.50 kg is pushed 2.20 along a frictionless horizontal table by a constant 16.0- N force directed 25.0 degree below the horizontal. Determine the work done by:
a. the applied force
b.the normal force exerted by the table
c.the force of gravity
d.the net force on the block
Physics Force & Laws Of Motion Level: Misc Level
When a car, moving at velocity v, collides with a light volley ball, initially at rest, the ball bounces off with a velocity of approximately: 2 v, -v ,v, 1.5 v, v /2
Physics Kinematics Level: Misc Level
You kick a soccer ball from level ground so that it will reach its maximum range Rmax. How high is the ball when it horizontal distance from the starting point is (3 /4) R max. Again find symbolically.
Physics Kinematics Level: Misc Level
You and two of your friends decide to have a race. You each start from the center of a circle and travel out along different radii at the same time. One of you moves with a constant speed of v1, the second starts from rest and moves with a constant acceleration a, and the third, moving with an initial speed v2, decelerates with constant acceleration -a. Show that if all of you reach the outside of the circle (meaning the same distance away from the center) at the same time then v2 =2v1. Find the acceleration symbolically.
Chemistry Physical Chemistry Level: Misc Level
Heat capacity data can be used to estimate the reaction enthalpy at one temperature from its value at another. Predict the standard reaction enthalpy of 2 NO2 (g)>>>>NO4(g)at 100 degrees C from its value at 25 degrees C which is -112.2 kJ /mol
Chemistry Physical Chemistry Level: Misc Level
Camping gas is typically propane.The standard enthalpy of combustion of propane gas is -2220 kJ /mol and the standard enthalpy of vaporization of the liquid is + 15 kJ /mol.Calculate the standard enthalpy and the standard internal energy of combustion of the liquid.
Chemistry Physical Chemistry Level: Misc Level
Given that the enthalpy of combustion of graphite is -393.5 kJ/mol and that of diamond is-395.41 kJ /mol calculate the standard enthalpy of the C (s,graphite) >>>>C(s, diamond) transition.
