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3 years ago

In which of the following is positive work done by a person on a suitcase

Physics

1 answer:

dolphi86 [110]3 years ago

6 0

The work done by man is positive as long as force applied by man on the suitcase and the displacement of suitcase are parallel. Since no other force is acting on suitcase other than gravitational force by Earth and force applied by man, ignoring force applied by moon and sun since they are negligible, if he holds suitcase still, then work done by him will be zero. If he lifts suitcase in upward direction, work done by him will be positive but work done by gravity will be negative since gravity acts towards the centre of the Earth and displacement of suitcase is opposite to that force.
Option 3 is interesting, if you are sitting on a chair(which is at rest) and analyzing the man holding the suitcase who is standing on moving walkaway, work done by man on case will be zero because displacement of case is in horizontal direction but force applied by man is upward. i.e, force and displacement are both perpendicular.

Hence option 2 is correct.

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Which of the following factors are involved in explaining why the energy of orbitals within a principle quantum level in multiel

Citrus2011 [14]

It looks like you have missed the necessary options for us to answer this question so I had to look for it. Anyway, here is the answer generally as the ℓ quantum number increases the energy is slightly higher. As a result 2s and 2p are no longer identical in energy in atoms<span> with more than one electron.</span>

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4 0

3 years ago

Fossil fuels like gasoline or coal are examples of

disa [49]

Answer:

Nonrenewable Resources

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3 years ago

A physics student throws a ball thrown horizontally from the top of a building with a speed of 8 m/s. The student measures the h

Alekssandra [29.7K]

Answer:

Following are the solution to the given question:

Explanation:

Please find the complete question in the attached file.

$a_x = 0\\\\a_y = -g = -9.81\ \ \frac{m}{s^2} \\\\v_{iy} = 0 \\\\y = v_{iy} \times t+ \frac{1}{2ay} \times t^2 \\\\ 15 = \frac{1}{2} \times 9.8 \times t^2 \\\\t = \sqrt{(2 \times \frac{15}{9.8})} \\\\$

$= 1.75 \ sec \\\\$

Distance:

$x = v_{ix} \times t \\\\$

$= 8 \times 1.75\\\\= 14 m$

4 0

3 years ago

A. What are the three longest wavelengths for standing waves on a 240-cm-long string that is fixed at both ends?

vovangra [49]

Answer:

a) the three longest wavelengths = 4.8m, 2.4m, 1.6m

b) what is the frequency of the third-longest wavelength = 75Hz

Explanation:

The steps and appropriate formula and substitution is as shown in the attached file.

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3 years ago

What type of bond results from the side‑on overlap of orbitals?

Serga [27]

Answer:

A pi bond

Explanation:

A pi bond is a type of covalent bond that results from the formation of a molecular orbital by the side-to-side overlap of atomic orbitals along a plane perpendicular to a line connecting the nuclei of the atoms.

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3 years ago