Answer:
a) per day
b)
c)
Explanation:
Given;
coefficient of performance of the refrigerator,
energy used per year of operation of the refrigerator,
a)
Energy used in single day:
per day
b)
Energy removed from the refrigerator in a single day:
We have the energy consumed in 1 day as,
so,
The desired effect of a refrigerator is to eliminate heat from the evaporator.
c)
Now the maximum mass of water that can freeze form 19.6°C:
where:
Answer:
correct answer is option d) 13 V and 0.46 A
Explanation:
given,
primary coil,
Number of turns N₁ = 1300
Voltage of the primary coil V₁ = 120 V
Current in the primary coil, I₁ =0.05 A
secondary coil,
Number of turns coil N₂ = 140
voltage calculation,
V₂ = 13 V
current calculation:
I₂ = 0.46 A
hence, correct answer is option d) 13 V and 0.46 A
Answer:
v=wavelength x f = 2 x 3 = 6 m/s
Explanation:
(a) 1800 N
The equation of the forces along the vertical direction is:
where
is the component of the applied force along the vertical direction
N is the normal force on the sled
mg is the weight of the sled
Substituting:
F = 1210 N
m = 246 kg
We find N:
(b) 0.580
The equation of the forces along the horizontal direction is:
where
is the horizontal component of the push applied by the mule
is the static frictional force
Substituting:
F = 1210 N
N = 1800 N
We find , the coefficient of static friction:
(c) 522 N
In this case, the force exerted by the mule is
So now the equation of the forces along the horizontal direction can be written as
where
and is the new frictional force, which is different from part (b) (because the value of the force of friction ranges from zero to the maximum value , depending on how much force is applied in the opposite direction)
Solving the equation,