Answer:
Explanation:
mass of backpack, m = 8.1 kg
weight of climber, W = 656 N
height raised, h = 9.4 m
time, t = 28.2 min = 28.2 x 60 = 1692 second
weight of backpack, w = m x g = 8.1 x 9.8 = 79.38 N
Work done by the climber on the backpack = mg x h = 79.38 x 9.4 = 746.17 J
Wok done in lifting herself + backpack = (W + w) x h
= (656 + 79.38) x 9.4 = 6912.57 J
Power developed by the climber,P = Total work / time
P = 6912.57 / 1692 = 4.09 W
Answer:k = 10.83 N/m²
Explanation: The angular frequency (ω), spring constant (k) and mass is related by the formulae below
ω = √k/m
But ω = 2πf, where f = frequency.
f = number of oscillations /time taken
Number of oscillations = 14, time taken = 11s
f = 14/11 = 1.27Hz.
ω = 2×22/7×1.27
ω = 7.98 rad/s.
By substituting this parameters into ω = √k/m
Where ω = 7.98rad/s, m = 170g = 170/1000 = 0.17kg.
7.98 = √k/0.17
By squaring both sides
(7.98)² = k/ 0.17
k = (7.98)² × 0.17
k = 10.83 N/m²
Yes. The main cause of polarization is by an external electric field. Polarization is characterized by an imbalance of charges where one end is more positive than the other end. When an electric field distorts the charges, there is a shift between the negative and positive poles. This causes the phenomenon called polarization.
Answer:
The correct answer is B.
The astronaut will know due to the light from the explosion.
Explanation:
Sound and vibrations require a medium such as air to travel through. Space, there is no air. Only a vacuum. So sound and vibrations are unable to travel. Light requires no medium to travel. It can go through a vacuum.
Therefore the Astronaut will see a bright flash of light as it travels from the explosion to outer space. It is also important to note that light can travel very far because nothing else interacts with its wave particles and as such, it cannot be impeded.
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