Answer:
4.5g/cm^3
Explanation:
Here, Mass(m)=67.5g
Volume(v)=15cm^3
Now, According to formula,
Density(p)=m/v
=67.5/15
=4.5g/cm^3
<h2>Answers:</h2><h2 /><h2>a) Arrow B</h2><h2>b) Arrow E</h2>
Explanation:
Refraction is a phenomenon in which a wave (the light in this case) bends or changes its direction <u>when passing through a medium with a refractive index different from the other medium.</u> Where the Refractive index is a number that describes how fast light propagates through a medium or material.
According to this, if we observe the rays A an D passing throgh the biconcave lens, we will have two mediums:
1) The air
2)The material of the biconcave lens
This two mediums have different refractive indexes, hence the rays will change the direction.
-For the incident ray A, the corresponding refractive ray is B, because is the ray that bends after passing throgh the lens
-For the incident ray D, the refracted ray is E following the same principle.
Answer:
Explanation:distance-time =speed
a,V =s/t
V=2m/2s
V=1m/s
b,v=s/t
V=80m/40s
V= 2m/s
The average speed is 2m/s
Parallel circuit
Advandages: 1. Every unit that is connected in a parallel circuit gets equal amount of voltage.
2. It becomes easy to connect or disconnect a new element without affecting the working of other elements.
3. If any fault happened to the circuit, then also the current is able to pass through the circuit through different paths.
Disadvantages: 1. It requires the use of lot of wires.
2. We cannot increase or multiply the voltage in a parallel circuit.
3. Parallel connection fails at the time when it is required to pass exactly same amount of current through the units.
series circuit
Advantages: 1. Series circuits do not overheat easily. This makes them very useful in the case of something that might be around a potentially flammable source, like dry plants or cloth.
2. Series circuits are easy to learn and to make. Their simple design is easy to understand, and this means that it’s simple to conduct repairs .
3. we can add more power devices, they have a higher output in terms of voltage .
4. The current that flows in a series circuit has to flow through every component in the circuit. Therefore, all of the components in a series connection carry the same current.
Disadvantages: 1.If one point breaks in the series circuit,the total circuit will break.
2. As the number of components in a circuit increases ,greater will be the circuit resistance.
Answer:
It would be hard to test scientifically since it's subjective and can only be proven true if you conducted some experimentations and observations.