Recent content by princesspriya

Homework Statement the largest of the Great Lakes, Lake Superior contains 1.2*10^16kg of fresh water, which has a specific capacity of 4186J/kg*C and a latent heat of fusion of 3.33*10^5J/kg. a.) If Lake Superior were still liquid at 0C, how much energy would need to be removed from the lake...

actually i figured it out. i was making a really stupid mistake... thanx for the help!

its not at the top o f its swing its at the lowest point so it will keep going.

well idk but my teacher said its 1.5 J.. and since its like swinging back it would be that velocity not the velocity at its lowest point.. i think

i thought it would be zero but than that would make the KE=0 which would not make sense

you cannot because you dont have the final velocity of the pendulum.

i see but back to the question now i feel so lost... no clue on how to solve it.

but i thought momentum is always conserved before and after the inelastic collision?

in the first one the total momentum's conserved but i would need to find the vf in order to use the equation and in the second one only total momentum is conserved the kinetic energy isnt since it would be a inelastic collision because they stick together.

Homework Statement An 9 g bullet is fired into a 2.5 kg pendulum bob which is initially at rest and becomes embedded in the bob. The pendulum then rises a vertical distance of 6cm. What was the initial speed of the bullet? What will be the kinetic energy of the pendulum when the pendulum...

the work done above water would be negative while the word done below water would be positive. but how can both of them have the same magnitude? that's the part i don't understand.

well when he is in water the work he does would be 1500N*5m because thats the distance he z traveling and the net force is 1500. so the work done would be 7500J. The work he does under water would not be the same as above water would it?

W=1009.5*(x+5) and W=490.5x are those two equations correct?

you cannot because you would have two unsolved, the work net and the distance.

well you dont know the distance so you cannot find the total work done.