A.) <span>If no unbalanced force acts upon the house of cards, then it will remain standing forever.
[ Other Statements doesn't make any sense in Physics, they can be true in some situation & can't be false, option A is the only answer ]
Hope this helps!</span>
The volume of a warmed part of the air is reduced and its density increases.
Explanation:
In a convective form of heat transfer, the volume of a warmed part of air is not reduced and its density does not increase.
During convection, heat causes the warm part of the air to expand and its volume increases. When volume increases, density is reduced.
- Convection is a form of heat transfer that involves the actual movement of particles of the medium.
- It usually occurs in fluids i.e gases and liquids.
- In convection, the cold part exerts a buoyant force on the warmer air below and causes it to rise.
- As the warmer part is rising the cooler part replaces it and a convective cell is formed in the process.
Learn more:
Energy transfer in the sun brainly.com/question/1140127
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1.
Answer:
Part a)

Part b)

Explanation:
Part a)
Length of the rod is 1.60 m
diameter = 0.550 cm
now if the current in the ammeter is given as

V = 17.0 volts
now we will have


R = 0.91 ohm
now we know that



Part b)
Now at higher temperature we have


R = 0.98 ohm
now we know that



so we will have



2.
Answer:
Part a)

Part b)

Explanation:
Part a)
As we know that current density is defined as

now we have

Now we have


so we will have

Part b)
now we have

so we have


so we have


The frequency of a genotype is how often it occurs. This can be obtained by:
number of occurrences / total population
= 160 / 1000
= 0.16 or 16%
Answer:
1.876 J
Explanation:
First, let’s calculate the compression of the spring from the Hooke’s law:
F=kx,
here, F=75 N is the force acted on the spring, k=1500 N⁄m is the force constant of the spring, x is the compression of the spring.
Then, we get:
x=F/k=(75 N)/(1500 N/m)=0.05 m.
Finally, we can find the potential energy stored in the spring:
PE=1/2 kx^2=1/2∙1500 N/m∙(0.05 m)^2=1.875 J.
correct my answer if it's wrong ^^