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# System Work

### Magnitude of the Impulse

A bullet, of mass 20g, traveling at 350 m/s, strikes a steel plate at an angle of 30degrees with the plane of the plate. it ricochets off at the same angle, at a speed of of 320 m/s. What is the magnitude of the impulse that the wall gives to the bullet? a. 300 Ns b. 0.3 Ns c. 0.52 Ns d. 6.7 Ns.

### Gravitation and Fluid Flow

(i) Please rewrite the equation attached, representing fluid flow in the presence of a buoyancy force.

### Working with two springs placed in series.

a 3-lb block can slide without friction in a slot and is connected to two springs of constant k_1=80 lb/ft and k_2=6 lb/ft. The springs are initially unstreatched when the block is pulled 2 in. to the right and released.Determine (a) the maximum velocity of the block, (b)the velocity of the block when it is 0.8 in. from its init

### Working with a block-pulley system

Please see the attached file for full problem description. Please use work concepts for solution. The solution should involve integration from 2 to 0 distance block travel. Please detail any calculus involved - if the response doesn't involve calculus, I would still like to see it, but please explain why since I am fairl

### Collisions

1. During a violent thunderstorm, hail of diameter 1.0 cm falls directly downward at speed of 25m/s. There are estimated to be 120 hailstones per cubic meter of air. (a) what is the mass of each hailstone ( density = 0.92 g/cm^3) ? (b) Assuming that the hail does not bounce fine the magnitude of the average force on a flat roof

### Newton's word problem

Jane, whose mass is 50.0kg, needs to swing accross a river(having width of D) filled with man-eating crocodiles to save Taezan from danger. She must swing into a wind exerting a constant horizontal force F on a vine having a length L and initially making an angle (theta) with the vertical. Taking D=50.0m F=110 N L=40.0m and

### Tension of a spring with two masses on it.

There are two masses hanging down off the sides of a table connected with a spring between them. Describe what will happen and what value the spring scale S will read (a spring scale will read the tension in the wire.) in fig.1 below if m 1 = m 2 = 1 kg and if m 1 = 1.2 kg, m 2 = 1 kg. For the second case show your work and

### Vectors and velocity: Landing speed for stone thrown from edge of a cliff

See attached file for a drawing. A student stands at the edge of a cliff and throws a stone horizontally over the edge with a speed of v(0) = 17.4 m/s. The cliff is h = 42.4 m above a flat horizontal beach. With what speed does it land? I don't understand how the stone could land with anything but the speed of gravity. Can

### A system of point charges

See attached file for graph. Four charges are placed at the corners of a square, where q is positive. Initially there is no charge in the center of the square. 1) Find the work, W required to bring the charge Qf from infinity and place it at the center of the square. 2) Find the magnitude of the electric force on th

### Electrostatic force and gravitational force in equlibrium.

Two identical spheres of mass 0.1 g each carrying identical charges are suspended from the same point by two weightless threads each of length 1.3 m. They position themselves so that their centres are 1.0 m apart. Find the charge on each sphere.