How does weight (in terms of w=mg) affect a wide and narrow grip pull ups? does velocity, acceleration, displacement have something to do with it?

A force of magnitude 750.0 N stretches a certain spring by 0.220 m from its equilibrium position. a)What is the force constant of this spring? b)How much elastic potential energy is stored in the spring when it is stretched 0.360 m from its equilibrium position. c)How much elastic potential energy is stored in the spring when it is compressed by 0.360 m from its equilibrium position? d)How much work was done in stretching the spring by the original 0.220 m ?

A 2000kg large boxcar that rolls without friction is sitting at rest. It is shot by a 20kg cannonball traveling 150m/s. What will the final velocity of the boxcar be in the following situations? a.) The cannon ball breaks through the boxcar walls and continues forward at 50m/s. b.) The cannonball breaks through one wall of the boxcar and then gets stuck inside the car. c.) The cannonball bounces off the boxcar wall rebounding with a reverse velocity of -50m/s. d.) Qualitatively explain why the boxcar ought to have the least speed when the cannonball passes through it and the most speed when the ball bounces?

A satellite has a mass of 6189 kg and is in a circular orbit 4.84 × 10⁵ m above the surface of a planet. The period of the orbit is 2.4 hours. The radius of the planet is 4.80 × 10⁶ m. What would be the true weight of the satellite if it were at rest on the planet’s surface?

W = ?

3. (a) The range of audible frequencies of sound in air, assuming sufficient amplitude, is from about 20 Hz to 20, 000 Hz. What is the range of audible wavelengths? Take the speed of sound in still air to be v = 344m/s.

(b) Sound is detected when the eardrum is caused to vibrate. The diameter of the eardrum is about 10 mm. Suppose a person whispers into your ear with an intensity, I = 10−8 W/m2 = E/(At), where E is the energy delivered to your eardrum, A is the area of the eardrum, and t is the duration of the whisper. i. What is the decibel level of the whisper ? ii. Calculate the area of the eardrum. How much energy, E, is delivered to the eardrum during 1 minute of the whisper ?

(c) A 1.5 metre long rope is stretched between two supports with a tension that gives a speed of transverse waves of 48 m/s. What is the wavelength and frequency of: i. the fundamental frequency? ii. the fourth harmonic?

(d) Two swift canaries fly towards each other, each moving at 15m/s relative to the ground, and each warbling a note of frequency 1,750Hz. i. What frequency does each canary hear from the note of the other? ii. What wavelength will each canary measure for the note of the other?

Common terns hover in a stationary position over the ocean watching for a tasty fish. When they see one, they immediately stop their wings and simply free-fall into the ocean to catch the fish. Calculate how long a fish near the surface has to move away after the instant a tern sees it from a height of 3 m above the surface. Repeat Problem above, but now include air resistance. Assume a ball of 3 cm radius with an average density of 4400 kg/m 3 , a density of air of 1.3 kg/m 3 , and a value of C = 1.

Given the following information about the Higgs boson Develop a scheme (in the form of Feynman diagrams) to produce it and detect it at the LHC (a proton-proton collider) A few givens/assumptions: • Its electrically neutral • Its mass = 125 GeV/c2 • Its coupling goes as the mass of the object it couples to. • It sucks to detect something if there are too many jets in the final state.

Hello, I am wondering how I can determine the direction in which a wave is travelling given a function I must verify if it first is a solution to the wave equation by finding the partial derivatives then I do not know how to extrapolate the direction and speed of a wave. Thanks

A motorist drives south at 26.0 m/s for 3.00 min, then turns west and travels at 25.0 m/s for 2.00 min, and finally travels northwest at 30.0 m/s for 1.00 min. For this 6.00 min trip, find the following values.

(a) total vector displacement
_____m (magnitude) ___° south of west

(b) average speed
____m/s
(c) average velocity
____m/s (magnitude) _____° south of west

Explain how the latest technology is used in the investigations of fingerprints, DNA, and firearms?

The mass flow rate of steam through an ideal Rankine turbine ( with an isentropic turbine and an isentropic pump) is 30lbm/s. The water and or steam is at a pressure of 1000 psia throughout the boiler and superheater and exits the superheater at a temperature of 600 F. The condenser is at a pressure of 2 psia, and the water exits the condenser as a saturated liquid. Calculate the following.

(a) the power output of the turbine

(b) the overall thermal efficiency of the cycle

(c) The Carnot efficiency of the cycle based on the boiler and condenser temperatures

3. There are several techniques for determining body composition. One method is hydrostatic weighing, or “underwater weighing”. To do this measurement, the person is weighed while standing in air on a regular scale and weighed again while completely immersed in water. By comparing these scale readings, the average density of the person can be calculated. From that density, the body fat percentage of the person can be calculated. Imagine you are a physical therapist, determining the body composition of a patient. The scale reading of your patient standing in air on a regular scale is 177 pounds, and while completely immersed in water is 2.5 pounds. NOTE: In this problem, a fair amount of precision is needed, so please: use g = 9.8 m/s2 , not the estimate of 10 m/s2 for converting units of force, use 1.0 pound = 4.45 Newtons

(a) Draw two free body diagrams of the patient: one when they are weighed in air on a regular scale, and one when they are weighed while immersed in water. Label each of the forces with its name.

(b) Determine the magnitude of each of the forces on your diagrams. (Recall the magnitude of a force is how big that force is.) Include units!

(c) Determine the mass of your patient. Include units!

(d) Determine the density of your patient. Give your answer both kilograms per cubic meter and in grams per cubic centimeter. Include units!

The body is made up of essentially two components: fat mass (the total fat of an individual) and fat-free mass (everything else: bone, water, lean tissue, etc.) Studies have determined that the densities of these two components are: Density of fat mass = 0.90 grams per cc Density of fat-free mass = 1.10 grams per cc (In physics, we write cubic centimeter as cm3 . In medicine, cubic centimeter is written as cc.) A person with a density of 0.90 g/cc would have 100% body fat, and a person with a density of 1.10 grams/cc would have zero percent body fat. Real people fall between these two extremes.

(e) Given the above information, assess your result for your patient’s density. Do you have confidence that your answer is reasonable? Explain why or why not.

(f) You discover that the scale reading of 2.5 pounds was actually obtained with the patient submerged in seawater, not fresh water. Which of the following is true? Circle one answer. Explain.

A. The calculated value of density is higher than the person’s actual density.

B. The calculated value of density is lower than the person’s actual density.

C. The patient’s density would be calculated correctly

Consider the data for a block of mass

m = 0.245 kg

given in the table below, which gives the position of a block connected to a horizontal spring at several times. Friction is negligible.

(a) What is the mechanical energy of the block–spring system?
J

(b) Write expressions for the kinetic and potential energies as functions of time. (Use the following as necessary: t. Assume K and U are measured in joules. Do not include units in your answer.)

Momentum, Impulse, and Collisions:

A 1050kg sports car is moving westbound at 15.0m/s on a level road, when it collides with a 6,320kg truck driving east on the same road at 10.0m/s. The two vehicles remain locked together after the collision.

What is the velocity (magnitude & direction) of the two vehicles just after the collision?

At what speed should the truck have been moving so that both it and the car are stopped in the collision?

Find the change in kinetic energy of the system of two vehicles for the situations of part a) and b). 

For which situation is the change in kinetic energy greater in magnitude?