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Various Physics (Mechanics) Problems

(See attached file for full problem description) --- 37. A block whose weight is 45.0 N rests on a horizontal table. A horizontal force of 36.0 N is applied to the block. The coefficients of static and kinetic friction are 0.650 and 0.420, respectively. Will the block move under the influence of the force, and, if so, what wi

Mathematical Conceptualization of Force, Mass, and Acceleration

A 810-kg car accelerates from rest to 27 m/s in a distance of 120 m. What is the magnitude of the average net force acting on the car? A 740 N B 2500 N C 91 N D 1300 N E 7900 N Two forces act on a 4.5-kg block resting on a frictionless surface as shown (see attached file). What is the magnitude of the

Classical Mechanics - Speed of a Ferry and Parabolic Curve of a ball

A ferry can travel at an optimal speed of 8 km/h in still water measured relative to the shore. What is the optimal speed of the ferry, relative to the shore, if it moves perpendicular to a 6 km/h current? A 4 km/h B 8 km/h C 10 km/h D 14 km/h E 28 km/h A baseball is hit upward and travels along a pa

Basic Math applications to Classical Mechanics

A park ranger wanted to measure the height of a tall tree. The ranger stood 6.10 m from the base of the tree; and he observed that his line of sight made an angle of 73.5° above the horizontal as he looked at the top of the tree. What is the height of the tree? A .5.84 m B 8.77 m C 11.7 m D 17.3 m E 20.6

Kinematics in Two Dimensions

11. You are driving into St. Louis, Missouri, and in the distance you see the famous Gateway-to-the-West arch. This monument rises to a height of 192 m. You estimate your line of sight with the top of the arch to be 2.0° above the horizontal. Approximately how far (in kilometers) are you from the base of the arch? 21. A

Mathematical Concepts

7. A tourist being chased by an angry bear is running in a straight line toward his car at a speed of 4.0 m/s. The car is a distance d away. The bear is 26 m behind the tourist and running at 6.0 m/s. The tourist reaches the car safely. What is the maximum possible value for d? 19. In getting ready to slam-dunk the ball, a

Kinematics and Vector Questions

I need some help with these two physics questions on vectors: 33. An ocean liner leaves New York City and travels 18.0° north of east for 155 km. How far east and how far north has it gone? In other words, what are the magnitudes of the components of the ship's displacement vector in the directions (a) due east and (b) due

Force Vectors and Work

11. You are driving into St. Louis, Missouri, and in the distance you see the famous Gateway-to-the-West arch. This monument rises to a height of 192 m. You estimate your line of sight with the top of the arch to be 2.0° above the horizontal. Approximately how far (in kilometers) are you from the base of the arch? 21.

Cyclist's speed at crest of hill & frictional force on motion

A 82.3-kg skier rides a 2860-m-long lift to the top of a mountain. The lift makes an angle of 16.6° with the horizontal. What is the change in the skier's gravitational potential energy? A cyclist approaches the bottom of a gradual hill at a speed of 28.7 m/s. The hill is 8.84 m high, and the cyclist estimates that she is go

Charges, spherical shell, and charge density

Please show all work and show all equations used and diagrams, etc. etc. so I understand completely please. 1) Charge is placed on the surface of a 2.7cm radius isolated conducting sphere. The surface density charge is uniform and has the value 6.9*10^-6C/m^2. The total charge on the sphere is: 2) A spherical shell has a

Electrostatic Forces and Movement of Charged Particles

Please show all work and diagrams plus equations used to solve problem. Thanks! 1) Particles 1, with charge q1 and 2, with a charge q2 are on the x axis, with particle 1 at x = a with and particle 2 at x=-2a. For the net force on a third charges particle, at the origin to be zero q1 and q2 must be related by q2=: (answer B

Object Charges and Forces

Please show all work and diagrams plus equations used to solve problem. Thanks! 1) A small object has charge Q. Charge q is removed from it and placed on a second small object. The two objects are placed 1 meter apart. For the force that each object exerts on the other to be a maximum, q should be: 2) Two small charged

Charged particles and net electrostatic force

Please show step by step solution you used to solve this problem and give the answer. Leave no details out! Even simple math! 1) The figure shows four situations in which five charged particles are evenly spaced along on an axis. The charge values are given except for the central particle, which has the same charge in all

Perturbation of a Negative Potential Time Dependent Problem

I am trying to calculate the probability that the n = 3 state will be excited at t = infinity for the case where b<<< a. and to show that for any value of b only the odd n states will be excited at t = infinity. My initial conditions and setup are: V(x,t) = Vinit(x) exp(-lambda times t) where I have a negative potential

Relativistic Momentum

A football player with a mass of 88 kg and a speed of 2.0 m/s collides head-on with a player from the opposing team whose mass is 120 kg. The players stick together and are at rest after the collision. Find the speed of the second player, assuming the speed of light is 3.0 m/s.

Spring Compression, Speed and Distance

6. [SJ3 7.P.024.] A toy cannon uses a spring to project a 5.30 g soft rubber ball. The spring is originally compressed by 5.00 cm and has a force constant of 7.80 N/m. When it is fired, the ball moves 16.0 cm through the horizontal barrel of the cannon, and a constant frictional force of 0.0320 N exists between barrel and ball.

Energy - Force and Work

A 90g bullet is fired from a rifle having a barrel 0.690m long. Assuming the origin is placed the bullet begins to move, the force (in newtons) exerted on the bullet by the expanding gas is 1000 + 6000x- 35000x*x where x is in meters. a) Determine the work done by the gas on the bullet as the bullet travels the length of the

The coordinates of the third mass ...

The center of mass of three objects is located at (1,0). One object with a mass of 5 kg is at (-2,-1) and a second object with a mass of 2 kg is at (0,0). Find the coordinates of the third mass of 3 kg. a.(1.7, 6.7) b.(2, 6) c. (1.3, 5.3) d. (6.7, 1.7)

Working with rotatinal inertia of a cylinder

A solid cylinder of mass 8kg and diameter 20cm is rotated about an axis parallel to its central axis at a distance of 10 cm from the cylinder. the rotatinal inertia of the cylinder about the parallel axis is: a. 0.12 kg m^2 b. 0.08 kg m^2 c. 12 kg m^2 d. 0.04 kg m^2

Rotational Work and Kinetic Energy - Speed and Height

A steel ball rolls down an incline into a loop-the-loop of radius R. (a) What minimum speed must the ball have at the top of the loop in order to stay on the track? (b) At what vertical height (h) on the incline, in terms of the radius of the loop, must the ball be released in order for it to have the required minimum speed at t

Spring Constant of the Spring

A 1200 kg car rolling on a horizontal surface has speed v = 66 km/h when it strikes a horizontal coiled spring and is brought to rest in a distance of 3.3 m. What is the spring constant of the spring?

Work & Energy - Average Force of Air Resistance

A softball having a mass of 0.25 kg is pitched at 114 km/h. By the time it reaches the plate, it may have slowed by 10 percent. Neglecting gravity, estimate the average force of air resistance during a pitch, if the distance between the plate and the pitcher is about 15 m.

Work and Energy (Force - Catapult)

A 20,000 kg jet takes off from an aircraft carrier via a catapult. The jet's engines exert a constant force of 136 kN on the jet. The force exerted on the jet by the catapult is plotted in Fig. 7-24b (see attachment) with F1 = 1200 kN and F2 = 73 kN. (a) Determine the work done on the jet by its engines during the launch of th

Work and Energy

If the work required to speed a car up from 10 km/h to 20 km/h is 5.0 x 10^3 J, what would be the work required to increase the car's speed from 20 km/h to 30 km/h?

Mechanics: Work done against friction

The problem is: The light horizontal spring has a force constant of k=100 N/m. A 2.00 kg block is pressed against one end of the spring (compressing it 0.100 m). The block is released and moves from rest 0.250 m to the right of the release position. Show that the coefficient of kinetic friction between the block and the horizont

Heat and work

From what height one would have to drop a block of ice so that the energy obtained would be enough to melt the block and raise the temp of the water to 50 C.

Easy EPE Problem

An electron and a proton are initially very far apart (effectively an infinite distance apart). They are then brought together to form a hydrogen atom, in which the electron orbits the proton at an average distance of 5.41 x 10-11m. What is EPEfinal - EPEinitial, which is the change in the electric potential energy?

The Continuity Equation

Petroleum flows along a 10-cm diameter pipeline at a speed of 2.0 m/s. Determine the flow rate, assuming the liquid is ideal.

A Cart on an Inclined Plane

A cart is on an inclined plane. If it is given a push up the ramp and released, then it moves up, reverses direction, and comes back down again. How will the kinetic energy change? How will the gravitational potential energy change? How will the mechanical energy change?