Answer:
a sound wave is an electromagnetic wave
Answer:
Part a)

Part b)

Part c)

Part d)
Net force on a closed loop in uniform magnetic field is always ZERO

Explanation:
As we know that force on a current carrying wire is given as

now we have
Part a)
current in side 166 cm and magnetic field is parallel
so we have

here we know that L and B is parallel to each other so

Part b)
For 68.1 cm length wire we have

here we know that


so we have


Part c)
For 151 cm length wire we have

here we know that


so we have


Part d)
Net force on a closed loop in uniform magnetic field is always ZERO

Answer:
proof in explanation
Explanation:
First, we will calculate the number of half-lives:

where,
n = no. of half-lives = ?
t = total time passed = 2100 million years
= half-life = 700 million years
Therefore,

Now, we will calculate the number of uranium nuclei left (
):

and the rest of the uranium nuclei will become thorium nuclei (
)

dividing both:

<u>Hence, it is proven that after 2100 million years there are seven times more thorium nuclei than uranium nuclei in the rock.</u>
4. Grass - Caterpillar - Hedgehog - Fox
5. Caterpillar, Rabbit, Mouse.
6. Cougar and Fox.
7. Bacteria
8. The bird, hedgehog, Fox and cougar would be effected since the Hedgehogs and birds would soon die out due to the loss of their food. Once they die out, the cougar and Fox would have no predators left to eat.