Energy is conventionally measured in calories as well as in joules. one calorie in nutrition is one kilocalorie, defined as 1 kcal = 4 186 j. metabolizing 1 g of fat can release 9.00 kcal. a student decides to try to lose weight by exercising. he plans to run up and down the stairs in a football stadium as fast as he can and as many times as necessary. to evaluate the program, suppose he runs up a flight of 100 steps, each 0.150 m high, in 62.5 s. for simplicity, ignore the energy he uses in coming down (which is small). assume that a typical efficiency for human muscles is 20.0%. therefore when your body converts 100 j from metabolizing fat, 20 j goes into doing mechanical work (here, climbing stairs). the remainder goes into extra internal energy. assume that the student's mass is 85.0 kg. (a) how many times must the student run the flight of stairs to lose 1.00 kg of fat?
Answers: 1
Physics, 22.06.2019 04:50, andrewsaul04
The position of a crate sliding down a ramp is given by x=(0.05t^3) m, y=(1.7t^2) m, z=(6−0.85t^5/2) m, where t is in seconds. (a) determine the magnitude of the crate's velocity when t = 2 s. (b) determine the magnitude of the crate's acceleration when t = 2 s.
Answers: 2
Physics, 22.06.2019 14:30, arianaaldaz062002
An electromagnet is a device in which moving electric chargers in a coil of wire create a magnet. whats one advantage of using electromagnetic in devices
Answers: 1
Physics, 22.06.2019 18:30, ptrlvn01
Two 2.0-cm-diameter disks face each other, 1.0 mm apart. they are charged to ±10 nc. what is the electric field strength between the disks? a proton is shot from the negative disk toward the positive disk. what launch speed must the proton have to just barely reach the positive disk?
Answers: 1
Physics, 22.06.2019 19:30, isiahb123
A47.2 g block of copper whose temperature is 480 k is placed in an insulating box with a 91.8 g block of lead whose temperature is 200 k. (a) what is the equilibrium temperature of the two-block system? (b) what is the change in the internal energy of the two-block system between the initial state and the equilibrium state? (c) what is the change in the entropy of the two-block system? the heat capacities of copper and lead are 386 j/kg·k and 128 j/kg·k, respectively.
Answers: 1
Energy is conventionally measured in calories as well as in joules. one calorie in nutrition is one...
Mathematics, 11.03.2021 14:00
Mathematics, 11.03.2021 14:00
Biology, 11.03.2021 14:00
Chemistry, 11.03.2021 14:00
Arts, 11.03.2021 14:00