A horizontal pipe of diameter 0.888 m has a smooth constriction to a section of diameter 0.5328 m . The density of oil flowing in the pipe is 821 kg/m3 . If the pressure in the pipe is 7620 N/m2 and in the constricted section is 5715 N/m2 , what is the rate at which oil is flowing? Answer in units of m3 /s.
Compare the force of gravity on a 81 kg mass on the Moon's surface with the force on the Earth's surface. Which force is greater? And by how much (F_Earth / F_Moon)? (Assume the mass of the Earth is 5.97 ✕ 1024 kg, the radius of the Earth is 6.38 ✕ 103 km, the mass of the Moon is 7.35 ✕ 1022 kg, and the radius of the Moon is 1.74 ✕ 103 km.)
A resistor R = 65.0-Ω is connected to the terminals of a battery with emf E =12.0 V & internal resistance r = 0.5 Ω.
(a) the current I in the circuit,
(b) the terminal voltage of the battery, Vab, and
(c) the power dissipated in the resistor R & in the battery’s internal resistance r. ( the solution should be simple not complicated)
A heavy nucleus Q of half-life 20 minutes undergoes alpha-decay with a probability of 60% and beta-decay with a probability of 40%. Initially, the number of Q nuclei is 1000. The number of alpha-decays of Q in the first one hour is
( a ) 50
( b ) 75
( c ) 350
( d ) 525
The arm of a crane at a construction site is 19.0 m long, and it makes an angle of 17.6 ◦ with the horizontal. Assume that the maximum load the crane can handle is limited by the amount of torque the load produces around the base of the arm. What maximum torque can the crane withstand if the maximum load the crane can handle is 632 N?
This exercise uses Newton's Law of Cooling.
A roasted turkey is taken from an oven when its temperature has reached 185°F and is placed on a table in a room where the temperature is 78°F.
(a) If the temperature of the turkey is 150°F after half an hour, what is its temperature after 45 min? (Round your answer to the nearest whole number.)
(b) After how many hours will the turkey cool to 100°F? (Round your answer to one decimal place.)