I need help with these questions

Question 1 of 15 - /1 E View Policies Current Attempt in Progress What is the spring constant of a spring that stores 12 J of elastic potential energy when compressed by 15 cm from its relaxed length? Number Units eTextbook and Media Save for Later Attempts: 0 of 10 used Submit Answer Using multiple attempts will impact your score. 10% score reduction after attempt 5Question 2 of 15 - /1 View Policies Current Attempt in Progress In the figure, a frictionless roller coaster car of mass m = 722 kg tops the first hill with speed vo = 12.6 m/s at heighth = 33.5 m. How much work does the gravitational force do on the car from that point to (a) point A, (b) point B. and (c) point C? If the gravitational potential energy of the car-Earth system is taken to be zero at C, what is its value when the car is at (d) Band (e) A? Firm (a) Number Units [b) Number Units (c) Number Units [d) Number Units (e) Number Units v eTextbook and Media Save for Later Attempts: 0 of 10 used Submit Answer-15 Question 3 of 15 Current Attempt in Progress You drop = 2.70 ke book to a friend who stands on the ground at distance D= 11.0 m below. If your friend's outstretched hands are at distanced - 1.50m above the ground (see the figure], (al how much work W, does the gravitational force do on the bookas it drops to her hands? (b) What is the change AU in the gravitational potential energy of the book-Earth system during the drop? If the gravitational potential energy of that system is taken to be zero at ground level, what is ((c) when the book is released and [d) when it reaches her hands? Now take ( to be 100 Jat ground level and again find (e) W,, (f ) AU, (x) Uat the release point, and (h) yather hands. (=) Number Units (bj Number Units (c] Number Units (d) Number Units (e) Number 1 Units (f Number Unit () Number Units (h] Number Units e Textbook and MediaQuestion 4 of 15 - /1 E View Policies Current Attempt in Progress Tarzan, who weighs 707 N, swings from a cliff at the end of a convenient vine that is 17 m long (see the figure). From the top of the cliff to the bottom of the swing he descends by 3.6 m. The vine will break if the force on it exceeds 1420 N. What would the greatest force on the vine be during the swing? Number 1 Units eTextbook and Media Save for Later Attempts: 0 of 10 used Submit Answer Using multiple attempts will impact your score. 10% score reduction after attempt 5Question 10 of 15 View Policies Current Attempt in Progress In the figure, a block of mass m = 20 ke is released from rest on a frictionless incline of angle 0 = 35% Below the block is a spring that can be compressed 4.3 cm by a force of 190 N. The block momentarily stops when it compresses the spring by 6.2 cm. (a) How far does the block move down the incline from its rest position to this stopping point? (b) What is the speed of the block just as it touches the spring? (a) Number Units (b) Number Units eTextbook and Media Save for Later Attempts: 0 of 10 used Submit Answer Using multiple attempts will impact your score. 10% score reduction after attempt 5Question 12 of 15 - /1 View Policies Current Attempt in Progress The boy in the figure here is initially seated on the top of a hemispherical ice mound of radius R = 14.0 m. He begins to slide down the ice, with a negligible initial speed. Approximate the ice as being frictionless. At what height does the boy lose contact with the ice? Number i Unit eTextbook and Media GO Tutorial Save for Later Attempts: 0 of 10 used Submit Answer Using multiple attempts will impact your score. 10% score reduction after attempt 5Question 13 of 15 - /1 View Policies Current Attempt in Progress A worker pushed a 39.0 kg block 8.10 m along a level floor at constant speed with a force directed 25.0' below the horizontal. If the coefficient of kinetic friction between block and floor was 0.420, what were (a) the work done by the worker's force and (b) the increase in thermal energy of the block-floor system? (a) Number Units (b) Number i Units eTextbook and Media Save for Later Attempts: 0 of 10 used Submit Answer Using multiple attempts will impact your score. 10% score reduction after attempt 5Question 14 of 15 - /1 Flew Policies Current Attempt in Progress A horizontal force of magnitude 35.2 N pushes a block of mass 4.28 ke across a floor where the coefficient of kinetic friction is 0.629. (a) How much work is done by that applied force on the block-floor system when the block slides through a displacement of 4.64 m across the floor? (b) During that displacement, the thermal energy of the block increases by 43.2 J. What is the increase in thermal energy of the floor? (c) What is the increase in the kinetic energy of the block? (a) Number 1 Units (b) Number i Units (c) Number 1 Units eTextbook and Media Save for Later Attempts: 0 of 10 used Submit Answer Using multiple attempts will impact your score. 10% score reduction after attempt 5Question 15 of 15 - /1 IE View Policies Current Attempt in Progress A 28 kg bear slides, from rest, 15 m down a lodgepole pine tree, moving with a speed of 4.7 m/s just before hitting the ground. (a) What change occurs in the gravitational potential energy of the bear-Earth system during the slide? (b) What is the kinetic energy of the bear just before hitting the ground? (c) What is the average frictional force that acts on the sliding bear? (a) Number Units (b) Number Units v (c) Number i Units v eTextbook and Media Save for Later Attempts: 0 of 10 used Submit Answer Using multiple attempts will impact your score. 10% score reduction after attempt 5