All categories

3 years ago

A weightlifter raises a 200-kg barbell through a height of 2 m in 2.2 s. the average power he develops during the lift is

2 answers:

4 0

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.

Liula [17]3 years ago

4 0

Answer:

Power, P = 1781.81 watts

Explanation:

It is given that,

Mass of the barbell, m = 200 kg

It is lifted to a height of, h = 2 m

Time taken, t = 2.2 s

We need to find the develops during the lift. We know that the pwer developed by an object is equal to the rate of doing work. Mathematically, it is given by :

$P=\dfrac{W}{t}$

$P=\dfrac{mgh}{t}$

$P=\dfrac{200\times 9.8\times 2}{2.2}$

P = 1781.81 watts

So, the average power developed during the lift is 1781.81 watts. Hence, this is the required solution.

You might be interested in

A wheelchair moves upward on a 7.1 degree ramp at a speed of 20km/h what is the horizontal velocity

Charra [1.4K]

Answer:

If the wheelchair is up 7.1 ft. In hight the time of flight should be 0.664 seconds and the distance should be 12.108 ft.

Explanation: I divided the displacement by the time and I used the equation Vx = 20 km/m

6 0

2 years ago

Giving a test to a group of students, the grades and gender are summarized belowGrades vs. Gender ABCMale10316Female465If one st

strojnjashka [21]

Answer:

20.45%

Explanation:

The probability that the student got a B is

$\frac{total\#of\text{ students that got B}}{\text{total students }}\times100\%$

Now, how many students are there in total?

The answer is

$10+3+16+4+6+5=44\; \text{students}$

How many students got a B?

The answer is

$3+6=9\; \text{students}$

therefore, the probability that the student has got a B is

$\frac{9\text{ students }}{44\text{ students }}\times100\%=20.45\%$

Hence, the probability that a student has got a B is 20.45%

5 0

1 year ago

What do we call fixed point around which a lever pivots?

xxTIMURxx [149]

Answer is A) Fulcrum

The fixed point that a lever rotates around is called the fulcrum.

4 0

1 year ago

Read 2 more answers

Apilot of mass 70 kg rides a fighter jet The fighter jet moves in a vertical circle of radius 100 m at a constant

Cerrena [4.2K]

Answer:

the force exerted by the seat on the pilot is 10766.7 N

Explanation:

The computation of the force exerted by the seat on the pilot is as follows:

$F = Mg + \frac{MV^2}{R}\\\\= 70 \times 9.81 + \frac{70 \times 120^2}{100}\\\\= 10766.7 N$

Hence, the force exerted by the seat on the pilot is 10766.7 N

4 0

3 years ago

2. Suppose that a parallel-plate capacitor has circular plates with radius R = 30 mm and a plate separation of d = 5.0 mm. Suppo

seropon [69]

Answer:

The maximum value of the induced magnetic field is $2.901\times10^{-13}\ T$ .

Explanation:

Given that,

Radius of plate = 30 mm

Separation = 5.0 mm

Frequency = 60 Hz

Suppose the maximum potential difference is 100 V and r= 130 mm.

We need to calculate the angular frequency

Using formula of angular frequency

$\omega=2\pi f$

Put the value into the formula

$\omega=2\times\pi\times60$

$\omega=376.9\ rad/s$

When r>R, the magnetic field is inversely proportional to the r.

We need to calculate the maximum value of the induced magnetic field that occurs at r = R

Using formula of magnetic filed

$B_{max}=\dfrac{\mu_{0}\epsilon_{0}R^2\timesV_{max}\times\omega}{2rd}$

Where, R = radius of plate

d = plate separation

V = voltage

Put the value into the formula

$B_{max}=\dfrac{4\pi\times10^{-7}\times8.85\times10^{-12}\times(30\times10^{-3})^2\times100\times376.9}{2\times130\times10^{-3}\times5.0\times10^{-3}}$

$B_{max}=2.901\times10^{-13}\ T$

Hence, The maximum value of the induced magnetic field is $2.901\times10^{-13}\ T$ .

7 0

3 years ago