3. A
4.B
3.Since the Earth rotates through two tidal “bulges” every lunar day, we experience two high and two low tides every 24 hours and 50 minutes
4.An eclipse of the Sun happens when the New Moon moves between the Sun and Earth, blocking out the Sun's rays and casting a shadow on parts of Earth
Given Information:
KEa = 9520 eV
KEb = 7060 eV
Electric potential = Va = -55 V
Electric potential = Vb = +27 V
Required Information:
Charge of the particle = q = ?
Answer:
Charge of the particle = +4.8x10⁻¹⁸ C
Explanation:
From the law of conservation of energy, we have
ΔKE = -qΔV
KEb - KEa = -q(Vb - Va)
-q = KEb - KEa/Vb - Va
-q = 7060 - 9520/27 - (-55)
-q = 7060 - 9520/27 + 55
-q = -2460/82
minus sign cancels out
q = 2460/82
Convert eV into Joules by multiplying it with 1.60x10⁻¹⁹
q = 2460(1.60x10⁻¹⁹)/82
q = +4.8x10⁻¹⁸ C
Explanation:
<u>Formula:</u>

<u>d = distance given</u>
<u>t</u><u> </u><u>=</u><u> </u><u>the amount of time </u><u>given</u>
<u>Substitute the given values into the formula for velocity</u><u>:</u>

velocity is shortened for v.
8 (distance) divided by 4 (time) equals the velocity.
<u>Solve:</u>

The velocity of the toy car equals: B. 2 m/s.
They should look for <span>a report from an independent scientific research firm,
even if they have to pay for it.
In preparing its report, the firm would have already surveyed many of the </span>
<span>citizens from several other towns that currently add fluoride to their water,
plus a lot of other relevant medical research on the subject.</span>