Answer:
189 Joules
Explanation:
Applying,
Q = cm(t₂-t₁)............. equation 1
Where Q = Heat, c = specific heat capacity of water, m = mass of water, t₁ = Initial Temperature, t₂ = Final temperature.
From the question,
Given: m = 15 grams = 0.015 kg, t₁ = 21 °C, t₂ = 24 °C
Constant: c = 4200J/kg.°C
Substitute these values into equation 1
Q = 0.015×4200×(24-21)
Q = 0.015×4200×3
Q = 189 Joules
Time taken for star to reach Earth = 7.5 years
<h3>Further explanation</h3>
Given
7.5 light years(distance Earth-star)
Required
Time taken
Solution
Speed of light=v = 3 x 10⁸ m/s
1 light years = 9.461 × 10¹⁵ m= distance(d)
So time taken for 1 light years :
time(t) = distance(d) : speed(v)
t = 9.461 × 10¹⁵ m : 3 x 10⁸ m/s
t = 3.154 x 10⁷ s = 1 years
So for 7.5 light years, time taken = 7.5 years
Yes, 50 pennies plus 50 pennies equals 100 pennies minus 50pennies equals 50 pennies.
A. Air expands, becomes less dense and rises when the temperature is high due to the increased kinetic energy. This causes the air molecules to move around much more so they are further apart.
