A weightlifter lifts a 1250-N barbell 2 m in 3 s.How much power was used to lift the barbell?
1 answer:
The power is 833.3 W
Explanation:
First of all, we need to calculate the work done in lifting the barbell, which is equal to the change in gravitational potential energy of the barbell:
where
mg = 1250 N is the weight of the barbell
h = 2 m is the change in height
Substituting,
Now we can calculate the power, which is equal to the work done per unit time:
where
W = 2500 J is the work done
t = 3 s is the time taken
Substituting,
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Answer:
Explanation:
given,
op-amp circuit with a gain of = (Av₁) = 96 V/V
Band width = (Bw₁) = 8 kHz
Required bandwidth(Bw₂) = 32 kHz
Highest gain available =(Av₂) = ?
For the given system Bandwidth product is constant
Av₁ Bw₁ = Av₂ Bw₂
96 x 8 = Av₂ x 32
the highest gain available under these conditions
Answer:
500 kg
Explanation:
It is given that,
The mass of a open train car, M = 5000 kg
Speed of open train car, V = 22 m/s
A few minutes later, the car’s speed is 20 m/s
We need to find the mass of water collected in the car. It is based on the conservation of momentum as follows :
initial momentum = final momentum
Let m is final mass
MV=mv
Water collected = After mass of train - before mass of train
= 5500 - 5000
= 500 kg
So, 500 kg of water has collected in the car.