Power is calculated as work per unit time, and work in turn is calculated as force multiplied by distance. In this case, the force required is equivalent to the weight of the barbell multiplied by acceleration due to gravity.
P = W/t = Fd/t = mgd/t = (200 kg)(9.81 m/s^2)(2 m)/2.2 s = 1783.64 Watts.
Answer:
0.33 Amp
8 Watts
Explanation:
The current through the 12 Ω resistor will be given by Ohm's law:
4 V / 12 Ω = 1/3 Amp ≈ 0.33 Amp
The power dissipated on the 2 Ω resistor can be calculated via the formula:
which gives:
4^2 / 2 = 8 Watts
Answer:
a. Both wires have the same resistivity
Explanation:
For the resistance of a wire , following formula holds good .
R = ρ l / S , R is resistance , l is length , S is cross sectional area and ρ is resistivity of the material that the wire is made of. Resistance is dependent on length and cross sectional area but resistivity does not depend upon length or cross sectional area . It only depends upon the type of material.
If we replace copper wire with aluminium wire , then resistivity will change .
Hence , since the wire remains made of copper , resistivity will not change.
31.3m/s
Explanation:
Given parameters:
Mass of rock = 40kg
Height of cliff = 50m
Unknown:
Speed of rock when it hits ground = ?
Solution:
We are going to use the appropriate motion equation to solve this problem
The rock is falling with the aid of gravitational force. The force is causing it to accelerate with an amount of velocity.
Using;
V² = U² + 2gH
V = unknown velocity
U = initial velocity = O
g = acceleration due to gravity = 9.8m/s²
H = height of fall
since the initial velocity of the bodyg is 0
V² = 2gH
V= √2gH = √2 x 9.8 x 50 = 31.3m/s
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Velocity brainly.com/question/4460262
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Answer:
I=0.0361 kg.m^2
Explanation:
Torque is the rotational equivalent of a force
Torque= perpendicular distance r X Force F
Torque T = I(moment of inertia) X α (angular acceleration)
T= Iα
r= 0.0285m
F= 1.9 x 10^3
T=0.0285 x 1.9 x 10^3
T= 54.15Nm
I=T/α
I=54.15/150
I=0.361 kg.m^2