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# Newton's Laws

### The force of hitting a baseball

A baseball (m= 149 g) approaches a bat horizontally at a speed of 40.2 m/s (90mi/h) and is hit straight back at a speed of 45.6 m/s (102 mi/h). If the ball is in contact with the bat for a time of 1.10 ms, what is the average force exerted on the ball by the bat? Neglecting the weight of the ball, since it is so much less than t

### What is the magnitude of the normal force?

A 35 kg crate rests on a horizontal floor, and a 65 kg person is standing on the crate. What is the magnitude of the normal force that the floor exerts on the crate and the crate exerts on the person?

### Physics: Force, mass, weight

See attached file for full problem descriptions: Force required to hold a flower pot board in place. Maximum mass that can be raised by a crane. Total weight of a seaside tower supported by a cable.

### Atmospheric pressure on a book which is lying on a table.

What is total downward atmospheric force on the top of a 0.21 m by 0.26 m book lying on a table? Why doesn't this force break the table?

### Finding speed of an automobile and the ratio of the drag force

The speed of an automobile increases from 80 km/h (50 mi/h) to 115 km/h (71 mi/h). What is the ratio of the drag forces at the two speeds?

### Classical Mechanics and Kinematics

I need some help with these questions with step-by-step explanations, look at attachment for full problem description: 63. A giant wheel, 40m in diameter, is fitted with a cage and platform on which a man can stand. The wheel rotates at such a speed that when the cage is at X (as shown) the force exerted by the man on the platf

### Momentum and Impulse Formulas

An engine of the orbital maneuvering system (OMS) on a space shuttle exerts a force of over a time interval of (see attachment), exhausting a negligible mass of fuel relative to the shuttle's mass of (see attachment) . 1. What is the y component of the impulse of the force for this time interval of (see attachment)? 2. W

### Value, Direction, and Balancing a Resultant Force

There are three people pushing on a box, as illustrated. Each of the three forces is 45 degrees from the x and y axes (there is no friction between the box and the floor). Picture of box is attached. The arrows are NOT to scale. a. Find the value and direction of the resultant force. b. What single force could be added to

A cylindrical specimen of steel with a cross section of 5 cm^2 is subjected to a tensile force of 800 N. What is the stress on the material?

### Calculate the net force of an object moving in a circle.

A 200 g object is moving in a circle with a radius of 4.0 m at a uniform speed of 6.0 ms. What is the net force acting on the object?

### Coefficient of Friction for Plastic Sliding on Wood

What is the coefficient of static and kinetic friction for plastic sliding on wood?

### Dragging box on the floor

Part 1. If I had a box with a mass (m) and dragged it across a level floor having a coefficient of kinetic friction uk by a rope that is being pulled upward at an angle (the symbol 0 with a one through it ) above the horizontal with a force of magnitude (F). In terms of M, uk, the symbol 0 with a line through it,l and g what

### Strings and Springs: Force Constant

When a 9.00 kg mass is placed on top of a vertical spring, the spring compresses 4.50 cm. Find the force constant of the spring.

### Block on inclined plane

Find the magnitude of the smallest horizontal force that would start the body moving (See attached for full question)

### Statics Problem : Force Diagrams, Magnitudes of Forces, Static Friction

Two blocks, of masses m1 and m2, are connected by a model string. Both blocks lie on a plane that is inclined to the horizontal at an angle [symbol1]. The part of the plane supporting the block of mass m1 is smooth, so that there is no frictional force. The upper part of the plane is rough, as that coefficient of the static fric

### Force Balance

Find the magnitude of the force and its direction along its line of action (See attached for full question)

### Force Balance

Find the magnitude of the reaction exerted by the lower fixture on the horizontal bar (See attached for full question and diagram)

### Calculating Normal force of Incline on the Block

My problem is that I need to determine the normal force of the incline on the block. The coefficient of static friction between the block and incline is mu^s = .295. I have determined that the minimum value of "F" is 18.49 N. I understand that "F" * sin (59.5) would be my answer to determine the normal force, yet I k

### Normal Force

What is the normal force of the incline on the block? (See attachment).

### Force and Free Body Diagrams

A person pushes a 13.0 kg lawn mower at constant speed with a force of 75.0 N directed along the handle, which is at an angle of = 48.0° to the horizontal (Fig. 4-38). Fig. 4-38. (a) Draw the free-body diagram showing all forces acting on the mower (b) Calculate the horizontal retarding force on the mower (N) (c) C

### Force of Crosswind on a High Sided Truck

High sided trucks are very vulnerable to cross winds on freeways. Consider a truck with a total weight of 1.5 x 10^5 Newtons, a length 15m, width 2m, and with sides of height 8m. Assume the pressure exerted by wind at speed v, hitting a vertical surface normally is pv^2, where p is the density of air (=1.2kg.m^-3). (a) Calcul

### Spring Constant of a Spring

Describe how the spring constant of a spring is related to the force exerted by the spring.

### Angle at which Compressive Force Becomes Zero

*Please see attachment for diagram. Question: The ball has a weight of 15 lb and is fixed to a rod having a negligible mass. If it is released from rest when theta = 0 deg., determine the angle theta at which the compressive force in the rod becomes zero.

### Calculating magnitude of force

Please do not include your response in a .pdf format, but Word documents are okay. Thanks! Here is the actual problem: A 1000 kg car pushes a 2000 kg truck that has a dead battery. When the driver steps on the accelerator, the drive wheels of the car push against the ground with a force of 4500 N. (a) What is the magnit

### Car on a banked curve

Q: A car rounds a banked curve where the radius of curvature on the road is R, the banking angle is A, and the coefficient of friction is F. Determine the range of speeds the car can have without slipping up or down the road.

### The Impulse Momentum Theorum for baseball: what is the average force exerted on the ball by the bat?

A baseball (m = 149 g ) approaches a bat horizontally at a speed of 40.2 m/s (90 mi/h) and is hit straight back at a speed of 45.6 m/s (102 mi/h). If the ball is in contact with the bat for a time of 1.10 ms, what is the average force exerted on the ball by the bat? Neglect the weight of the ball, since it is so much less than t

### The normal force, Static and Kinetic Frictional Forces

A 35-kg crate rests on a horizontal floor, and a 65-kg person is standing on the crate. Determine the magnitude of the normal force that (a)the floor exerts on the crate and (b) the crate exerts on the person.

### Finding the resultant force - a crash test

The sensor in the torso of a crash-test dummy records the magnitude of the net external force acting on it. If the dummy is thrown forward with a force of 130.0 N while simultaneously being hit from the side with a force of 4500.0 N, what force will the sensor report? I would like the formula used to solve this problem a

### Propulsive force of large caliber aircraft gun used by German Air Force in WW2

The largest caliber aircraft gun operated by German Air Force in WW2 was the 12.8cm flak 40. The weapon fired a 25.8kg shell with a muzzle speed of 880m/s. What propulsive force was necessary to attain the muzzle speed within the 6.00m barrel (assume the shell moves horizontally w/consistant acceleration and neglect friction).

### Force of pressure at the top of the tank inside a hot water heat

The water in the plumbing of a house is at a gauge pressure of 300,000 Pa. What force does this cause on the top of the tank inside a water heater if the area of the top is 0.2m (exponent 2)?