Answer:
48.22 kg
Explanation:
Applying the law of conservation of momentum,
Total momentum before collision = Total momentum after collision
Note: Since both skaters were initially at rest, then their total momentum before collision is equal to zero.
And the velocity of the second skater will be in opposite direction to the first.
0 = mv+m'v'.................... Equation 1
Where m = mass of the first skater, m' = mass of the second skater, v = final velocity of the first skater, v' = final velocity of the second skater.
make v' the subject of the equation
m' = -mv/v'................. Equation 2
Given: m = 62 kg, v = 0.7 m/s, v' = -0.9 m/s (opposite direction to the first)
Substitute into equation 1
m' = -62(0.7)/-0.9
m' = 48.22 kg
B.
This equation quantifies the inter convertibility of mass and energy and helps us understand the large amount of energy that would be released if mass were converted to energy.<span />
Answer:
20 MHz
Explanation:
Since speed of radio waves = speed of light = c and for a wave, v = fλ where v = speed of wave, f = frequency and λ = wavelength.
Given that λ = 15 m and v = c = 3 × 10⁸ m/s
f = v/λ
substituting the values of the variables into the equation, we have
f = v/λ = 3 × 10⁸ m/s ÷ 15 m
= 0.2 × 10⁸ Hz
= 2 × 10⁷ Hz
= 20 × 10⁶ Hz
= 20 MHz
<span>The reaction force would be the exact opposite of the action. In this case, choice (c) would be the most correct. If the action is the ball pushing the glove, the reaction would then be the glove pushing back on the ball.</span>
It is converted to energy according to E =mc^2