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Classical Mechanics

Physics question: projectile motion

A soccer player kicks a ball at an intial speed of 11.0 m/s at an angle of 40.0 degrees to the ground. a) How far will the ball travel horizontally? b) How long is it in the air?


Question: When an object weighing 50 N is hung from a vertical spring, it stretches 20 cm. Calculate the spring's elastic constant. If the 50 N load were replaced with a 80 N weight, how far would the spring stretch?

Kinematics: Two Locomotives

Two locomotives approach each other on parallel tracks. Each has a speed of v = 80 km/h with respect to the ground. If they are initially d = 9.0 km apart, how long will it be before they reach each other?

Kinematics: Motion Down and Incline

Do 12a and b. Well tell me how you figure out what vo is and the rest of the variables, the physics part, how you set the problem up, and do all the math and solve with an answer. Thanks.

Kinematics: A Rock Thrown Downwards

A rock is thrown straight downward with an initial speed of 3m/s into a well. As the same time, the bucket 110 meters down at the bottom of the well is raised at a speed of 2m/s. Determine how far the rock has fallen when it hits the bucket. (Use g = 10 m/s^2).

Pascal's Principle

The digging bucket on a large mechanical excavator is moved by a piston sliding within a single hydraulic cylinder. According to the manufacturer, the hydraulic fluid in the cylinder is pressurized to 1000 psi (6.895 x 10^6 Pa or 68 atm) by a pump. The cylinder has a diameter of 0.165 m and a stroke of 1.36 m. Determine the ma

Critical stress, stress field

Question 3 Tensile tests of an elastic material show that it has a Young's modulus of... Please see attached past exam questions

Poisson Ratio, Young's modulus

Please see attached past exam questions: (a) A material has a shear modulus of 4.615.... (b) Hence show that Young's modulus is...

Mechanics and Young's Modulus

For the cross-section of the following figure, which is made from material with Young's modulus 100MN/m^2: (a) State the location of the centroid. (b) Show that the second moments of area about the z axis and teh axis aa are respectively 2.51x10^5 mm^4 and 1.26x10^6 mm^4. (c) A strut is made of this section. When subject to

CT scanner

A CT scanner has to be able to form an image within a 40cm diameter image area. The spatial sampling along each profile is 1mm. What angular resolution (the angle between projections) is required to match this sampling distance at the boundary of the image area?

Tension on a bridge cable

A knight in armour on a horse leaves the castle. His squire has mistakenly lowered the drawbridge 20 degrees below the horizontal. The knight and his horse stop when their combined center of mass are 1 metre from the end of the bridge. The uniform bridge is 8 metres long and has a mass of 2000 kg. The lift cable is attached t

Hitting a Tennis Ball

The tennis ball has a horizontal speed of 15 m/s when struck by the racket. If it then travels away at an angle of 25 degrees from the horizontal and reaches a maximum altitude of 10m, measured from the height of the racket, determine the magnitude of the net impulse of the racket on the ball. The ball has a mass of 180g. Neglec

Loaded Sullivan's Perfect Ratchet

Show that in the case of zero external force the equation v=(fL/kT)^2 D/L (e^(fL/kT) - 1 - fL/kT)^-1 reduces to 2D/L. Then show that at high force (but still smaller than (epsilon/L)) the equation reduces to v=(fL/kT)^2 D/L (e^(-fL/kT)).

Sliding Box

The 30-lb box A is released from rest and slides down along the smooth ramp and onto the surface of a cart. If the cart is fixed from moving, determine the distance s from the end of the cart to where the box stops. The coefficient of kinetic friction between the cart and the box is uk= 0.6.

Volume and density problem

A block of wood half as dense as water floats with half its volume above water. A piece of iron is then tied on top so the wood floats with only 1/4 its volume above surface. If the wood and iron are turned over so that the iron is submerged beneath the wood, then the volume of wood above the water surface will be? Why?

Classical mechanics problems - vectors operations and uniform acceleration

13. A bus travels at an average speed of 90 km/h. On average, how far does the bus travel in 20 min? Is this distance the magnitude of the actual displacement of the bus? Explain. 17. A student runs 30 m east, 40 m north, and 50 m west. (a) The magnitude of the student's net displacement is (1) between 0 and 20 m, (2) bet

Projectile motion

A missile is launched at a speed of 25 m/s at an angle of to 35the ground. What is its range? How high did it go vertically? Answer without using calculus.

Uniform cylinder, moment of inertia by translation of axis.

A uniform cylinder, has mass 18 kg and radius .5 m. Its moment of inertia about an axis which is .3 m from the center of mass axis, is 3.87 kg m^2. Each axis is perpendicular to the circular face of the cylinder. Find the moment of inertia about an axis at the surface of the cylinder.

Kinematics problem

A car travels 600. m one way with a speed of 40. m/s and then travels 600. m in another way at 20. m/s.What is the car's average speed? (Caution: The answer is not 30. m/s.)

What is the largest mass Tarzan can have and swing safely across the river?

Tarzan tries to cross a river by swinging from one bank to the other on a vine that is 10.0 m long. His speed at the bottom of the swing, just as he clears the surface of the river, is 8.0 m/s. Tarzan does not know that the vine has a breaking strength of 1.0 x 10^3 N. What is the largest mass Tarzan can have and make it safe