Physics Answers

A heater marked 60°c evaporates 6x10¯³ kg of boiling water in 60 seconds and what is the specific latent heat of vaporization of water in Jkg¯¹

Calculate the one temperature at which Fahrenheit and Celsius thermometers agree with each other

Directions: In this activity you will be able to calculate the electric charges using the superposition principle. Solve the following problems. Show your solutions.

1. Three point charges, which are equally separated by a distance of 20cm, are arranged along the y-axis in a vacuum. The topmost charge bears a charge of -4.0μC, the middle charge has a charge of 3.0μC, and the bottom carries a 7.0μC. What is the magnitude and direction of the net electrostatic force that the middle charge experiences.

2. Find the force of attraction between two ball bearings with charges of 6μC and 14μC mm apart from each other.

A parachutist of mass 70 kg jumps from a plane at an altitude of 32 km above the surface of the Earth. Unfortunately, the parachute fails to open. (In the followingparts, neglect horizontal motion and assume that the initial velocity is zero.)

(a) Calculate the time of fall (accurate to 1 s) until ground impact, given no air resistance and a constant value of g.

(b) Calculate the time of fall (accurate to 1 s) until ground impact, given constant g and a force of air resistance given by

Directions: Solve the following problems stated below. Show your solutions.

a. A -1.49x10^-8 C charge is separated from a -1.15x10^-9 C charge by a distance of 2.01x10^20 m. Determine the repulsive force between the two charges.

b. Two charges (-2.09x10^-18 C and 1.60x10^-19 C) are separated by a distance of 4.01x10^-10 m. Compute the force of attraction between them.

Water is flowing in a fire

hose with a velocity of 1.0 m/s and a pressure of 200000 Pa. At the nozzle the

pressure decreases to atmospheric pressure (101300 Pa), there is no change in

height. Use the Bernoulli equation to calculate the velocity of the water

exiting the nozzle. (Hint: The density of water is 1000 kg/m3 and

gravity g is 9.8 m/s2. Pay

attention to units!)]

1. An unknown wire experiences an electric field of 10 V/m, and has a current density of 5.0 ✕ 10⁷ A/m² . What is the resistivity of the wire?

How to replace the three forces acting on the 3D bracket by a single equivalent force?

A 92.2 g blue jay flies through the trees in order to land at a bird feeder. If it flies with a constant speed of 24.0 km/h and makes a tight horizontal turn with a radius of 3.50 m, how much centripetal force must its wings exert to

make the turn?

Gabby is driving her 2400kg Mercedes on a rainy night (Oh, no…!) at a constant rate of 83km/hr when she sees a tree branch lying across the road 60 meters ahead and applies the brakes in a hurry (there will be some skidding involved, I fear). The coefficient of kinetic friction is 0.41.

1. Will Gabby stop before hitting the branch? What will the actual stopping distance be? 
2. How much time will be required to stop? 
3. What will be the average deceleration rate?