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dem82 [27]
3 years ago
9

A load of 800 N is lifted using a block and tackle having 5 pulleys. If the applied effort is 200 N, calculate

Physics
2 answers:
ser-zykov [4K]3 years ago
8 0

Explanation:

Load=800N

Effort=200N

1. Mechanical Advantage = LOAD/EFFORT

= 800N/200N

= 4

2 Velocity Ratio = no. Of pulleys =5

3. Efficiency = Mechanical advantage / velocity ratio × 100%

= (4/5)×100%

=80%

4. output work= load×load distance

= 800N × 5m

= 4 × 1000J

5. Efficiency = (output work/input work) ×100%

Or, 80% = (4000J/input work) ×100%

Or, 80%/100% = 4000J/inputwork

Or, 4/5 = 4000J/inputwork

Or, input work =4000J × 5/4

Input work = 5×1000J

I hope it helped! ;-)

never [62]3 years ago
4 0

Answer:

I got the same answers.

Explanation:

I agree with the first person respone.

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Pie

Answer:

1060.41kg/m^3

Explanation:

Bulk modulus is defined as the relative change in the volume of a body produced by a unit of compressive acting uniformly over its surface:

B=\rho _o \frac{\bigtriangleup P }{\bigtriangleup \rho}

Hence the density of the seawater at a depth of 680atm is calculated as:-

\rho=\rho_o +\bigtriangleup \rho=\rho_o(1+\frac{\bigtriangleup P}{B})\\\\=1030 \times (1+ \frac{(680-1)\times10^5}{2.3\times 10^9})\\=1060.41kg/m^3

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3 years ago
A roundabout in a fairground requires an input power of 2.5 kW when operating at a constant angular velocity of 0.47 rad s–1 . (
natita [175]

Answer:

Explanation:

Since the roundabout is rotating with uniform velocity ,

input power = frictional power

frictional power = 2.5 kW

frictional torque x angular velocity = 2.5 kW

frictional torque x .47 = 2.5 kW

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= 5.32 kN . m

= 5 kN.m

b )

When power is switched off , it will decelerate because of frictional torque .

5 0
3 years ago
Write short letters.
Svetradugi [14.3K]

Answer:

No. 67

Peter Street

12th Road

Chennai

24th June 201_

Dear Amrish

I have come to know that since your school has closed for the Autumn Break you have plenty of free time at your disposal at the moment. I would like to tell you that even I am having holidays now.

It has been a long time since we have spent some time together. If you are free, I would welcome to have your company this weekend. Why don’t you come over to my house and spend a day or so with me?

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4 0
3 years ago
Read 2 more answers
A 6.00 g lead bullet traveling at420 m/s is stopped by a large
Westkost [7]

Answer:

The increase in temperature of the bullet is 351.1 kelvin

Explanation:

First, we should find the kinetic energy of the bullet is:

K=\frac{mv^{2}}{2}=\frac{(6\times10^{-3}\,kg)(420\,\frac{m}{s})^{2}}{2}

with m the mass and v the velocity.

K=529.2 J

Now we know that half of the kinetic energy of the bullet is transformed into internal energy, by second's law of thermodynamics that means heat (Q) to raise bullet temperature (T), so:

Q=\frac{K}{2}= 264.6\,J

To know what the increase in temperature is, we should use specific heat of lead:

c=125.604 \frac{J}{kg\.K}

The equation that relates specific heat, change in temperature and mass is:

Q=cm\varDelta T

solving for \varDelta T:

\varDelta T=\frac{Q}{cm}=\frac{264.6}{(125.604)(6\times10^{-3})}

\varDelta T= 351.10\, K

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The force of gravity acting<br> on a child's mass on earth is 490 newtons. what's the child's mass?
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What we know:
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- Force: 490 N

Equation derived:
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6 0
3 years ago
Read 2 more answers
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