Answer: 1 cal is 4.186 J, 1 kcal = 4186 J A : 1014 m , B 200 m
Explanation: A) Work done by climber is change in potential energy.
W = ΔEp = mgh = 67.0 kg· 9.81 m/s²· h = 160 kcal · 4186 J / kcal.
Solve h = 160 kcal · 4186 J / kcal /67.0 kg· 9.81 m/s² = 1014 m
B Energy is only 20 % : Then h = 0.20 ·160 kcal · 4186 J / kcal /67.0 kg· 9.81 m/s² = 200 m.
Actually, muscles also produce heat from most of the energy provided by food.
Answer:
0.03 s
Explanation:
The maximum force is 90 N, and the mass is 0.2 kg, so we can find the deceleration:
F = ma
-90 N = (0.2 kg) a
a = -450 m/s²
The initial velocity is 14 m/s, and the final velocity is 0 m/s, so the time is:
v = at + v₀
0 m/s = (-450 m/s²) t + 14 m/s
t = 0.03 s
The fastest she can slow it down to a stop without breaking it is in 0.03 s.
B)............... Have a good day, Have a nice day:)
Answer:
Current = 2 Amperes
Explanation:
Given the following data;
Resistance = 8 Ohms
Power = 32 W
To find the amount of current going through the speaker;
Mathematically, power can be calculated using the formula;
Power = current² * resistance
Substituting into the formula, we have;
32 = current² * 8
Current² = 32/8
Current² = 4
Taking the square root of both sides, we have;
Current = √4
Current = 2 Amperes