# finding

1. ### Troublesome problem with finding the electric current

In this problem we have A wire with resistance per unit length of 32 Ω/m that is bent at a right angle. The second straight fragment of the same wire (The blue one) moves at the top of the first one at a speed of v = 4 m/s. The whole system is located in a magnetic field with an induction of B =...
2. ### Finding the electric field along the line between charges

Hey So I've been asked this question as part of my physics assignment (Its an advanced section question so significantly harder than the normal questions) and I've been stuck, my intuition tells me there should be two zero points, and initially I found a formula that only found one, however...
3. ### Finding optical power of corrective lenses?

The question is as follows: "A person with presbyopia has a near point of 40 cm. This person wears glasses to correct their vision such that they can comfortably read the screen of their mobile phone when it is held 25 cm from their eyes. If this person wears their glasses such that they sit...
4. ### Finding new Reynold's Number (Re) with decrease and increases in percentages

This is the OG question: "A small hose in a machine carries a viscous fluid. When the machine is first turned on the fluid flows through the hose and the Reynold's number is 1800. As it warms up, there is a reduction of the density of the fluid of 1.61%, a reduction in the viscosity of...
5. ### Finding density of an object with the weight and density of fluid?

Hello, I am a bit stuck with a question "A large container of water initially reads 0.485 kg. A ball is hung in the air from another set of scales which initially read 0.112 kg. The ball is lowered until it is fully submerged. The readings on both scales are now 0.496 kg and 0.101 kg...
6. ### Finding the power used to change phase?

I have figured the heat added to the system so far, but can't figure out where to go from here to get the change in internal energy to work out the work(W)? https://imgur.com/a/4SiM6fd It is question number 3 right at the bottom of the photo. Thank you for any help.
7. ### (Photoelectric effect) Finding velocity of ejected electron given wavelengths

Hey, I'm in my senior year of highschool and I'm stuck on this problem that deals with things I haven't even learned (Canadian education system for ya). It has to do with the photoelectric effect. Given the wavelengths of an X-ray before and after it strikes an unknown metal...
8. ### Finding area of solar collector

Hi, I was wondering if someone could help me with this question: The total electric generating capacity of Canada is 81GW. What is the area (in km^2) of horizontal photovoltaic solar collector that could satisfy this need? Note the average insolation on a horizontal surface is 4.8kWh/m^2 for a...
9. ### Finding volumetric flow rate of heat engine

A Heat Engine has a thermal efficiency of 40% at a steady power output of 30kW. Calculate the required volumetric fuel flow in L/Hr ( litres/hour) if the fuel has a density of 850 kg/m^3 and an energy content of 45 MJ/kg.
10. ### Finding Charge given expression for Electric Potential

Hi, I'm having some trouble with a problem I have regarding electric potential. I'm given the equation for the electric potential everywhere on the xy plane. V=(22/√((x+1.54)^2+y^2))-(38/√(x^2+(y-2.77)^2)) There are two particles which I need to find the charge and coordinates for. I...
11. ### Finding a position vector of a pivot on a lever from its torque

Hi guys, I have a problem here which I'm really stumped on. I have a rigid rod of 3.1m length, with two equal masses at either end. The pivot is placed so that the total torque is 25k N.m about the pivot, and I need to find it's location. I've drawn a diagram, a basis, calculated that the...
12. ### Finding the mass of the planet

Hi, I'm doing an independent course, so whenever I need help with a question it is very difficult to find it. The lesson I am on now has given me a question that I have no clue how to begin working on. Basically, a team of space explorers lands on a planet with a radius of 7.5*10^6 m. A...
13. ### Finding an expression for the velcoity v as a function of time.

Here's the problem: Suppose an object with mass m is projected with initial velocity v 0 along the horizontal direction. Assume quadratic air resistance of the form F drag = αv^2 , where F drag is the magnitude of the drag force. Find an expression for the velocity v as a function of time...
14. ### Help and explination when finding the Ampere :)

Hey! :) Im doing some homework and i get confused about this mission. As you see, i have drawed my idea in the right corner, but i have come up with another idea.. and that is if the ampere goes the lowest resistance way? Or the way i drawed... I appriciate feedback and any sort of help!:)...
15. ### Finding the Ampere!! :)

Hey! :) Im doing some homework and i get confused about this mission. As you see, i have drawed my idea in the right corner, but i have come up with another idea.. and that is if the ampere goes the lowest resistance way? Or the way i drawed... I appriciate feedback and any sort of help!:)...
16. ### Finding centre of gravity using moments

Can someone please answer Question 13, i do not understand how to approach it.
17. ### Finding melting rate of a ice cube?

How do i find how long it takes to melt an ice cube? can i use this heat transfer equation below i took the weight of the ice cube and was gonna melt the ice cube in a controlled environment (microwave) and find the rate the heat is transferred from the wattage of the microwave. and i...
18. ### Finding time for velocity ( water hammer related)

Hello, The problem is given: I first found v0(final) from: v0=sqrt(\frac {2*g*h}{lambda*\frac {l}{d}+1}) v0=sqrt(\frac {2*9.81*18}{0.03*\frac {400}{2}+1}) v0 is 7.1 m/s 90% of v0 is v= 6.39 m/s. Time to reach v=6.39 m/s: t=\frac {l*v0}{2*g*H}*log(\frac {v0+v}{v0-v}) t=\frac...
19. ### Finding cycle-time for irregular pipe

Hello everyone, The problem is : I started with the following: rho*g*(z1*sin(theta1)-z2*sin(theta2)*A=-rho*A*l*\frac {dv}{dt} After Area and density cancellations: g*(z1*sin(theta1)-z2*sin(theta2))+l* \frac {dv}{dt}=0 Adjusting datum to balanced fluid level...
20. ### Finding temperature before combustion

Hi All, I'm completely stuck :( I've been trying to find the temperature of air in an otto cycle before the fuel is ignited. I know exhaust air is 733^C, Cp is 1005, air flow mass rate is 0.00460 fuel mass flow rate is 0.000393. The cal val for fuel is 46.5 Mj/kg, and im using...