Answer:
Mechanical Advantage is 2
Explanation:
M.A = length of ramp / height of ramp
= 2/1
=2
Answer:
Corect answer is D
Explanation:
Assuming that the C
O
2 gas is behaving ideally, therefore, we can use the ideal gas law to find the pressure increase in the container by:
P
V=nRT ⇒ P=n
R
T
/V
n=no of moles of the gas = mass/molar mass
Molar mass o f C
O
2=44g/mol, mass = 44g
mole n = 1mole
T=20C=293K
R=0.0821L.atm/mol.K
P=nRT/V
P = 1 x 0.0821 x 293/2
P = 12atm
Answer:
Mass = 18.0 kg
Explanation:
From Hooke's law,
F = ke
where: F is the force, k is the spring constant and e is the extension.
But, F = mg
So that,
mg = ke
On the Earth, let the gravitational force be 10 m/
.
3.0 x 10 = k x 5.0
30 = 5k
⇒ k = 
................ 1
On the Moon, the gravitational force is 
of that on the Earth.
m x 
= k x 5.0
= 5k
⇒ k = 
............. 2
Equating 1 and 2, we have;
=
m = 
= 18.0
m = 18.0 kg
The mass required to produce the same extension on the Moon is 18 kg.
Answer:
Newton's law of cooling states that the rate of heat loss of a body is directly proportional to the difference in the temperatures between the body and its surroundings. The law is frequently qualified to include the condition that the temperature difference is small and the nature of heat transfer mechanism remains the same. As such, it is equivalent to a statement that the heat transfer coefficient, which mediates between heat losses and temperature differences, is a constant. This condition is generally met in heat conduction (where it is guaranteed by Fourier's law) as the thermal conductivity of most materials is only weakly dependent on temperature. In convective heat transfer, Newton's Law is followed for forced air or pumped fluid cooling, where the properties of the fluid do not vary strongly with temperature, but it is only approximately true for buoyancy-driven convection, where the velocity of the flow increases with temperature difference. Finally, in the case of heat transfer by thermal radiation, Newton's law of cooling holds only for very small temperature differences.
When stated in terms of temperature differences, Newton's law (with several further simplifying assumptions, such as a low Biot number and a temperature-independent heat capacity) results in a simple differential equation expressing temperature-difference as a function of time. The solution to that equation describes an exponential decrease of temperature-difference over time. This characteristic decay of the temperature-difference is also associated with Newton's law of cooling
