Recent content by oMovements

I did this but the answer comes out to be: 95 = Eout / 360000 x 100 0.95 = Eout / 360000 Eout = 342000 This would mean 342000J of thermal energy is produced by a 100W bulb However, this answer is 95J which you only get when you use time in hours. So maybe the answer is wrong at the back of the...

Homework Statement An incandescent bulb is only 5.0% efficient. How much waste thermal energy is porudced by a 100.0W bulb in 1.0h? (Anwer=95J)Homework Equations P = E/T Efficiency = Eout/Ein x 100%The Attempt at a Solution P = E/T E = PT...

I don't understand how you came up with that equation.

Homework Statement The force of gravity at Earth's surface on an astronaut is 634N. What is the force of gravity on the same person at each of the following distances, in multiples of Earth's radius, from the centre of Earth? a) 2 b)5 c)10 d)17.2 I have no idea how to solve this, can...

Force of 15N

What other way can I solve the tension in the string without equating the 2 equations? I still got the correct answer using this method by the way. I'm also still confused how to solve c)

15N. There is an acceleration because the it states "Students measure the maximum force of static friction as 21.4N to move both objects across a horizontal surface." and static friction can also cause an object to move if I remember correctly.

I still do not understand why Fg=18.1. I know that the hanging mass must have a maximum net force of 18.1N without the block moving. However, shouldn't Ft-Fg=18.1 because those are the two forces acting on the hanging mass. Or is Fg=18.1 because the acceleration is zero, therefore so is the net...

Homework Statement A string is tied to a 4.4 kg block and 120g hanging bucket. Students add 20g washers one at a time to the bucket. The student are unaware that the coefficient of static friction for the block on the table is 0.42. A) what is the maximum force of static friction for the...

Homework Statement Two objects are made of identical material and are tied together with string. The first object has a mass of 5.0kg and the second object has a mass of 3.0kg. Students measure the maximum force of static friction as 31.4N to move both objects across a horizontal surface. a)...

Since the cable breaks, the net force would become Fk=200N since there is no tension. a= Fnet/m = 200/125 a= 1.6 m/s/s To find the velocity when the cable breaks, I would have to determine the final velocity when t=5 and acceleration is 1.2m/s/s a = vf-vi/t 1.2 = Vf-0/5 Vf = 6 m/s...

How would I find these new values?

Thanks, I understand that. But how would I solve c), would time still be 5s when it comes to a stop?

I don't understand why the initial velocity is zero when the cable breaks. Also what formula would I use?

Homework Statement An electric motor is used to pull a 125kg box across a floor using a long cable. The tension in the cable is 350N and the box accelerates at 1.2 m/s/s [fwd] for 5.0s. The cable breaks and the box slows down and stops a )Calculate the coefficient of kinetic friction...