Answer:
63.57 kg
Explanation:
weight = 140 lbs
Let the mass is m.
1 lbs = 4.45 N
The weight of an object is defined as the force with which our earth attracts the body towards its centre.
Weight is the product of mass of the body and the acceleration due to gravity of that planet.
W = m x g
On earth surface g = 9.8 m/s^2
Now convert lbs in newton
So, 140 lbs = 140 x 4.45 = 623 N
So, m x 9.8 = 623
m = 63.57 kg
Thus, the mass is 63.57 kg.
Solar energy and Geothermal energy are your answers :)
6. D
7. D
8. B
let me know if you need clarification
Answer:
The fall in temperature of the liquid is 8.6 +/- 0.1 ⁰C
Explanation:
Given;
initial temperature of the liquid, t₁ = 76.3 +/- 0.4⁰C
final temperature of the liquid, t₂ = 67.7 +/- 0.3⁰C
The change in temperature of the liquid is calculated as;
Δt = t₂ - t₁
Δt = (67.7 - 76.3) +/- (0.3 - 0.4)
Δt = (-8.6) +/- (-0.1)
Δt = 8.6 +/- 0.1 ⁰C
Therefore, the fall in temperature of the liquid is 8.6 +/- 0.1 ⁰C