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Suppose that the steel gas tank in your car is completely filled when the temperature is 16 °C. How many gallons will spill out of the 88-Liters tank when the temperature rises to 40 °C?
A ball is thrown horizontally from a building 63.0 m high with a speed of 25.0 m/s. Find the (a)vertical and horizontal components of the ball's initial velocity, (b) time flight, (c) distance from the foot of the building where the ball will strike the ground, and (d) velocity when the ball will strike the ground.
A conductor having a cross-sectional area of 0.00161 sq in. carries. a current of 4.5 amp. Calculate the electron velocity, assuming the wire to be (a) copper, (b) aluminum.
Calculate the equivalent resistance for the circuit which is connected to 24V battery and also find the potential difference across 4ohms and 6ohms resistors in the circuit.
Eight boys are equally spaced about a pushball and each exerts a force upon it toward the center, as shown. Each boy in position 1, 3, and 7 exerts a force of 70 N, and the rest of the boys exert 50 N each. What force is needed to keep the ball at rest? *
A football is kicked vertically upward from the ground and a student gazing out of a window sees it coming passed him at 16ft/sec. The window is 30ft above the ground.
a. How high does the ball go above the ground?
b. How long does it take to go from a height of 30ft to the highest point?
A screw jack, 25% efficient and having a screw of pitch 0.4cm is used to raise a load through a certain height. If I’m the process the handle turns through a circle of radius 40cm, calculate the
i) velocity ratio of the machine
ii) The mechanical advantage of the machine
iii) Effort required to rise a load of 1000N with the machine. (take π = 3.14)
Draw a block and tackle system of pulleys with a velocity ratio of 5 . A block and tackle with a velocity ratio of 5 is used to raised a mass of 25 kg through a vertical distance of 40 cm at a steady rate. If the effort is equal to 60 N, determine
a)the distance moved by the effort;
b)the work done by the effort in lifting the load;
c)the loss in energy involved in operating the machine.
A) How much work is done in lifting a 30 kg box from a point A on the
ground to a point B on a platform 1.5 m directly above A?
B) Show that the same amount of work would be done if the box were
carried from ground level by sliding the box along a smooth 3.0 m long plank whose one end rests on the ground away from A and the other end rests on point B.
A skier, starting from rest, skis down a slope from a height of 300 m to the horizontal ground level.
a) Show that the speed with which the skier reaches the ground level does
not depend on either the mass of the skier or the angle of incline of the slope. State any assumptions made.
b) Calculate the speed with which the skier reaches the ground level.
