What is the minimum energy needed to change the speed of a 1,084-kg sport utility vehicle from 12.5 m/s to 37.5 m/s? Give your answer in Joules.

6 .A 32.0 kg child slides down a long slide in a playground. She starts from rest at a height h1 of 17.00 m. When she is partway down the slide, at a height h2 of 9.00 m, she is moving at a speed of 9.50 m/s.   Calculate the mechanical energy lost due to friction (as heat, etc.).

A 58-kg pole vaulter running at 10 m/s vaults over the bar. Her speed when she is above the bar is 1.4 m/s. Neglect air resistance, as well as any energy absorbed by the pole, and determine her altitude as she crosses the bar. ____m

A student evaluates a weight loss program by calculating the number of times she would need to climb a 10.0 m high flight of steps in order to lose one pound (0.45 kg) of fat. Metabolizing 1.00 kg of fat can release 3.77 x 10'J of chemical energy and the body can convert about 21.2% of this into mechanical energy (the rest goes into internal energy.) HINT (a) How much mechanical energy (in J) can the body produce from 0.450 kg of fat? (b) How many trips up the flight of steps are required for the 52.0 kg student to lose 0.450 kg of fat? Ignore the relatively small amount of energy required to return down the stairs. trips Need Help? Read It Watch It

At what rate is a 58.64-kg boy using energy when he runs up a flight of stairs 9.37-m high, in 6.79 s?

they asked us to use conservation of mechanical energy concepts for this question

Similar to the previous problem, we heat about a cup (230 g) of milk (we'll treat it like water, with a specific heat of 4186 J/kg °C) from refrigerator temperature (5.2 °C) to a comfortable drinking temperature (52.5 °C) in order to make a cup of hot chocolate. First, find the energy required to heat this milk. Next, imagine giving a 1,600 kg truck this same amount of kinetic energy. What speed (in m/s) will the truck be travelling?

A student spends part of his day walking between classes, during which time he expends energy at an average rate of 525 W. The remainder of the day he is sitting in class, studying in library, or resting during break; during these activities, he expends energy at an average rate of 178 W. If he expends a total of 8.3 x10^7 J energy in a 24-hour day, how much of the day did he spend walking?

Samantha wishes to maintain her weight and goes to the gym to work off the calories she consumed at breakfast that morning. She lifts a 28.0-kg barbell from shoulder level to above her head, through a vertical height of 0.550 m. How many times must she lift the barbell to make up for the 3.25  102 Calories of energy she consumed at breakfast? Note that Calories refers to food calories. (Include lowering the barbell as well.) The answer is NOT 9

Problem 4: Energy that is not utilized for work or heat transfer in the human body is converted to the chemical energy of body fat, which contains about 39 kJ/g. How many grams of fat will you gain if you eat 2650 kcal one day and do nothing but sit relaxed for 16.0 h and sleep for the other 8.00 h? (Assume sleeping burns 1.2 kcal/min, while sitting relaxed burns 1.7 kcal/min.) mfat =