<span>1.) It is 6.00km from your home to the physics lab. As part of your physical fitness program, you could run that distance at 10.0km/hr (which uses up energy at the rate of 700W ), or you could walk it leisurely at 3.00km/hr (which uses energy at 290 W).
A.)Which choice would burn up more energy?
running or walking?
b.)How much energy (in joules) would it burn?
c.)Why is it that the more intense exercise actually burns up less energy than the less intense one?
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Answers
billrussell42
Best Answer: running, at 10 km/hour for 6 km is
6 km / 10 km/hour = 0.6 hour or 36 min
energy used is 700 watts or 700 joules/s x 36 min x 60s/min = 1.512e6 joules or 1.5 MJ
walking, at 3 km/hour for 6 km
6 km / 3 km/hour = 2 hour or 120 min
energy used is 290 watts or 290 joules/s x 120 min x 60s/min = 1.872e6 joules or 1.8 MJ
C) should be obvious
PS, this has nothing to do with potential energy.
billrussell42 · 5 years ago
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Simon van Dijk
I assume the watt consumption is per hour. Then running 6km at 10.0 km/h results in 700*6/10 = 420 w.h and walking in 290*6/3 = 580 w.h So walking would burn up more energy (kwh)
b) 1 kilowatt hour = 3 600 000 joules
so 420 wh = 0.42 kwh = 1.51.10^6 joule
c) when you put more effort in making the distance your energy is used more efficient.
Simon van Dijk · 5 years ago
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Answer:
Height of coffee mug = 5 cm
Explanation:
Changing all the data given in to unit cm
50 mm = 5 cm
20 cm = 20 cm
8 m = 800 cm
0.1 km = 100 m = 10000 cm
Since we need to find the height of coffee mug, it's height will not be more than 10 cm.
So 5 cm is the correct choice.
Answer:
33.48 V
Explanation:
Parameters given:
Number of turns, N = 420
Magnetic field strength, B = 0.055 T
Area, A = 0.065 m²
Angular velocity, ω = 22.3 rad/s
EMF induced in a coil is given as:
EMF = -dΦ/dt
where Φ = magnetic flux
Magnetic flux, Φ, is given as:
Φ = B * N * A * cosωt
EMF = -d( B * N * A * cosωt) / dt
EMF = B * N * A * ω * sinωt
where ωt = 90°
Therefore:
EMF = 0.055 * 420 * 0.065 * 22.3 * sin90°
EMF = 33.48 V
