All categories

2 years ago

A box with the mass of 20 kg at 5 m is lifted to 20 m. How much work was 7 points done?

Physics

1 answer:

kirza4 [7]2 years ago

3 0

Answer:

$2,900\: \mathrm{J}$

Explanation:

Work is given by the equation $W=F\Delta x$ where $F$ is force and $\Delta x$ is displacement.

Displacement is defined as change in position. In this case, the box moves from 5m to 20m. Its displacement is $20-5=15\:\mathrm{m}$ .

The force acting on the box is the force of gravity, given as $F_g=mg$ .

Therefore, the total work done is:

$W=F\Delta x=mg\Delta x = 20\cdot 9.81\cdot 15=2,943=\fbox{$2,900\:\mathrm{J}$}$ (two significant figures).

You might be interested in

Which will result in positive buoyancy and cause the object to float?

Wewaii [24]

the answer should be:

When the buoyant force is equal to the force of gravity

4 0

2 years ago

Read 2 more answers

Jesse wants to know how well a particular brand of car wax protects his car from dirt. What is the independent variable ?

miv72 [106K]

The brand of car wax

4 0

2 years ago

If you fall from a building onto a net which extends the time of impact by 10 times, what happens to the force you experience?

zubka84 [21]

Answer:

A larger impulse. A 1-kg ball has twice as much speed as a 10-kg ball.

Explanation:

6 0

2 years ago

The smallest unit of charge is − 1.6 × 10 − 19 C, which is the charge in coulombs of a single electron. Robert Millikan was able

vovangra [49]

Answer:

$-8.0 \times 10 ^{-19 }\ C,\ -3.2 \times 10 ^{-19 }\ C, -4.8 \times 10 ^{-19 }\ C$

Explanation:

<u>Charge of an Electron</u>

Since Robert Millikan determined the charge of a single electron is

$q_e=-1.6\cdot 10^{-19}\ C$

Every possible charged particle must have a charge that is an exact multiple of that elemental charge. For example, if a particle has 5 electrons in excess, thus its charge is $5\times -1.6\cdot 10^{-19}\ C=-8 \cdot 10^{-19}\ C$

Let's test the possible charges listed in the question:

$-8.0 \times 10 ^{-19 }$ . We have just found it's a possible charge of a particle

$-3.2 \times 10 ^{-19 }$ . Since 3.2 is an exact multiple of 1.6, this is also a possible charge of the oil droplets

$-1.2 \times 10 ^{-19 }$ this is not a possible charge for an oil droplet since it's smaller than the charge of the electron, the smallest unit of charge

$-5.6 \times 10 ^{-19 },\ -9.4 \times 10 ^{-19 }$ cannot be a possible charge for an oil droplet because they are not exact multiples of 1.6

Finally, the charge $-4.8 \times 10 ^{-19 }\ C$ is four times the charge of the electron, so it is a possible value for the charge of an oil droplet

Summarizing, the following are the possible values for the charge of an oil droplet:

$-8.0 \times 10 ^{-19 }\ C,\ -3.2 \times 10 ^{-19 }\ C, -4.8 \times 10 ^{-19 }\ C$

5 0

2 years ago

The force that probably propels the movement of the earth s gigantic rock plates is

il63 [147K]

The correct answer is:

c. convection.

The heating of magma and the continuous cycle of evolution of the magma creating a convection current is the reason for the evolution of Earths tectonic plates.

Explanation:

Tectonic plates are ready to move because the Earth's lithosphere has higher strength than the underlying asthenosphere. Lateral density changes in the mantle appear in convection. Plate movement is believed to be driven by a succession of the motion of the seafloor apart from the extended ridge (due to variations in topography and density of the crust.

4 0

2 years ago