All categories

4 years ago

1) Which of the following explains why a bicycle uses a gear?

2 answers:

7 0

1. "The gear decreases effort force" is the one among the following choices given in the question that <span>explains why a bicycle uses a gear. The correct option among all the options is option "C".

2. A can opener is a compound machine. The correct option among all the options that are given in the question is the second option or option "B".</span>

Marta_Voda [28]4 years ago

4 0

Answer:

1) D. The gear decreases resistance force

2) B. A car opener

Explanation:

1): A bicycle uses a gear to decrease the resistance force as when the gears are shifted, the chain moves from a larger ring to a smaller one thus reducing the surface area of the ring as well as friction which results into a greater speed by applying same amount of effort.

2): As a compound machine is a combination of more than one simple machine. Out of all the options, a car opener is said to be a compound machine as it consist of a lever, screw, wedge and axle and wheel.

These are some of the simple machines which combines to make a complex machine ( car opener ).

You might be interested in

A student lifts a box of books 2 meters with a force of 45 N. He then carries the box 10 meters to the living room. What is the

Alisiya [41]

Answer:

90J

Explanation:

The only time work is being done is when he lifts the box off the ground. Therefore, using the work formula, 2 x 45, you get 90J. Hope this helps someone.

5 0

3 years ago

Question:

iogann1982 [59]

The correct answer is:
<span>C: in the protons and neutrons of an atom

In fact, the nuclear energy refers to the binding energy of the nucleons (protons and neutrons) of an atom. The protons and the neutrons are held together by the strong nuclear interaction, one of the four fundamental forces of nature, and the energy associated to this interaction is called nuclear energy.

</span>

7 0

3 years ago

Once water has been heated to its boiling point, additional heating will not raise its temperature. what happens to this additio

solong [7]

A. Energy was used to change phase of water from liquid to gas (evaporation). it is radiated back into the atmosphere from the stove.
This is because water evaperates after reaching it's boiling point.

4 0

3 years ago

Read 2 more answers

In which list below do the experimental steps appear in the order in which they are done?

fgiga [73]

The answer is B . You begin with a purpose for the lab, then hypothesize on what you believe will happen. Next, follow the procedures. This is always the last step, Anatoly did. Reflect upon you hypothesis, did the lab support or disprove your hypothesis. Include observations you have made. Identify errors.

5 0

3 years ago

Two small plastic spheres are given positive electrical charges. When they are a distance of 14.8cm apart, the repulsive force b

sdas [7]

Answer:

Explanation:

Case I: They have same charge.

Charge on each sphere = q

Distance between them, d = 14.8 cm = 0.148 m

Repulsive force, F = 0.235 N

Use Coulomb's law in electrostatics

$F=\frac{Kq_{1}q_{2}}{d^{2}}$

By substituting the values

$0.235=\frac{9\times10^{9}q^{2}}{0.148^{2}}$

$q=7.56\times10^{-7}C$

Thus, the charge on each sphere is $q=7.56\times10^{-7}C$ .

Case II:

Charge on first sphere = 4q

Charge on second sphere = q

distance between them, d = 0.148 m

Force between them, F = 0.235 N

Use Coulomb's law in electrostatics

$F=\frac{Kq_{1}q_{2}}{d^{2}}$

By substituting the values

$0.235=\frac{9\times 10^{9}\times 4q^{2}}{0.148^{2}}$

$q=3.78\times10^{-7}C$

Thus, the charge on second sphere is $q=3.78\times10^{-7}C$ and the charge on first sphere is $4q = 4\times 3.78\times 10^{-7}=1.51 \times 10^{-6} C$ .

6 0

3 years ago