Answer: f=150cm in water and f=60cm in air.
Explanation: Focal length is a measurement of how strong light is converged or diverged by a system. To find the variable, it can be used the formula:
= (nglass - ni)(
-
).
nglass is the index of refraction of the glass;
ni is the index of refraction of the medium you want, water in this case;
R1 is the curvature through which light enters the lens;
R2 is the curvature of the surface which it exits the lens;
Substituting and calculating for water (nwater = 1.3):
= (1.5 - 1.3)(
-
)
= 0.2(
)
f =
= 150
For air (nair = 1):
= (1.5 - 1)(
-
)
f =
= 60
In water, the focal length of the lens is f = 150cm.
In air, f = 60cm.
Answer:
T = 20.84°C
Explanation:
From the law of conservation of energy:
Heat Lost by Copper Block = Heat Gained by Aluminum Calorimeter + Heat Gained by Water

where,
= mass of copper = 227 g
= mass of water = 844 g
= mass of aluminum = 155 g
= specific heat capacity of calorimeter = 385 J/kg.°C
= specific heat capacity of water = 4200 J/kg.°C
= specific heat capacity of aluminum = 890 J/kg.°C
= change in temperature of copper = 283°C - T
= change in temperature of water = T - 14.6°C
= change in temperature of aluminum = T - 14.6°C
T = equilibrium temperature = ?
Therefore,

<u>T = 20.84°C</u>
Answer:
1.137278672 m/s
+5.9 cm or -5.9 cm
Explanation:
A = Amplitude = 6.25 cm
m = Mass of object = 225 g
k = Spring constant = 74.5 N/m
Maximum speed is given by

The maximum speed of the object is 1.137278672 m/s
Velocity is at any instant is given by

The locations are +5.9 cm or -5.9 cm
C it takes a lot of capital to get the windmills and the fields of windmills set up
Momentum = (mass) x (speed)
Original momentum = (700 kg) x (30 m/s) = 21,000 kg-m/s
Final momentum = (700 kg) x (15 m/s) = 10,500 kg-m/s
Change in momentum = - 10,500 kg-m/s .