# 7 the answer is 4) because you need opposites in order to attract
# 8 I'm going to guess it is 4) because electricity is needed in order a light bolt to work.(don't take my word for this one I'm not sure but, the other answer are correct)
# 9 the answer is 4) because the comb dose collect negative charges from the hair in order to make the hair have positive charge.
Hope this helped : )
The speed of an electron when it moves in a circular path perpendicular to a constant magnetic field is 8.88 x 10^7 m/s.
The angular momentum(L) of an electron moving in a circular path is given by the formula,
L = mvr ........(i)
We know that the radius of the path of an electron in a magnetic field is
r = mv/qB
Putting this value in equation (i),
L = mv x mv/qB
or L = (mv)^2/qB
Putting the given values in the above equation,
4 x 10^-25 = (9.1x10^-31)^2 x v^2/ 1.6 x 10^-19 x 1 x 10^-3
v comes out to be 8.88 x 10^7 m/s.
Hence, the speed of an electron when it moves in a circular path perpendicular to a constant magnetic field is 8.88 x 10^7 m/s.
To know more about "angular momentum", refer to the following link:
brainly.com/question/15104254?referrer=searchResults
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Answer:
It will take 126.84 years to pay off the debt
Explanation:
Total debt = $14,000,000,000,000.00
Paid $3,500 per second
Number of seconds to pay off the debt will be:
14 ×10^12 /3500
Number of seconds = 4× 10^9 seconds
Converting seconds to year:
I second = 3.171 ×10^-8 calendar year
Therefore, number of years it will take to pay off $14 Trillion =( 4 ×10^9 ) × ( 3.171 × 10^-8)
Number of years = 126.84 years
thank you so much for the schlatt
Given :
Reem took a wire of length 10 cm. Her friend Nain took a wire of 5 cm of the same material and thickness both of them connected with wires as shown in the circuit given in figure. The current flowing in both the circuits is the same.
To Find :
Will the heat produced in both the cases be equal.
Solution :
Heat released is given by :
H = i²Rt
Here, R is resistance and is given by :
So,
Now, in the question every thing is constant except for the length of the wire and from above equation heat is directly proportional to the length of the wire.
So, heat produced by Reem's wire is more than Nain one.
Hence, this is the required solution.
