Answer:
a) Weight of the rock out of the water = 16.37 N
b) Buoyancy force = 4.61 N
c) Mass of the water displaced = 0.47 kg
d) Weight of rock under water = 11.76 N
Explanation:
a) Mass of the rock out of the water = Volume x Density
Volume = 470 cm³
Density = 3.55 g/cm³
Mass = 470 x 3.55 = 1668.5 g = 1.6685 kg
Weight of the rock out of the water = 1.6685 x 9.81 = 16.37 N
b) Buoyancy force = Volume x Density of liquid x Acceleration due to gravity.
Volume = 470 cm³
Density of liquid = 1 g/cm³
c) Mass of the water displaced = Volume of body x Density of liquid
Mass of the water displaced = 470 x 1 = 470 g = 0.47 kg
d) Weight of rock under water = Weight of the rock out of the water - Buoyancy force
Weight of rock under water = 16.37 - 4.61 =11.76 N
<span>The maximum possible efficiency, i.e the efficiency of a Carnot engine , is give by the ratio of the absolute temperatures of hot and cold reservoir.
η_max = 1 - (T_c/T_h)
For this engine:
η_max = 1 - [ (20 +273)K/(600 + 273)K ] = 0.66 = 66%
The actual efficiency of the engine is 30%, i.e.
η = 0.3 ∙ 0.664 = 0.20 = 20 %
On the other hand thermal efficiency is defined as the ratio of work done to the amount of heat absorbed from hot reservoir:
η = W/Q_h
So the heat required from hot reservoir is:
Q_h = W/η = 1000J / 0.20 = 5000J</span>
Answer:
<h2>3 m/s^2</h2>
Explanation:
Step one:
given
Mass m= 4kg
Force F= 12N
Required
Acceleration the relation between force, acceleration, and mass is Newton's first equation of motion, which says a body will continue to be at rest or uniform motion unless acted upon by an external force
F=ma
a=F/m
a=12/4
a=3 m/s^2
Yes the answer is correct
they are added vectorially. If htere is a resultant force, the thing acclerates. If they vectorially add to zero, thing doesn't move
