Answer:
Gravity can never be zero.
Explanation:
The graph shows that the force of gravity is always present despite the amount of distance, indicating that gravity will never be 0. Note, however, that gravity can be extremely small as the distance increases. The limit of the force of gravity as the distance approaches infinity is 0, but never actually touches this value.
Answer:
The complete question contains 2 parts such that
part a: Where the probe is submerged in water. In this case the wattage of heater is 90.47 W
part b: Where the probe is on a vessel. In this case the wattage of heater is So 121.34 W
Explanation:
Part a
For the first part when it is assumed that the probe is submerged in the water. In this case the heat loss is only due to the convective heat transfer which is given as

Here
- Q is the heat loss which is to be calculated
- A is the area of the body which is given as
. It is calculated as

- Tbody is 10 C
- Tsurr is 0C
- h is the convection coefficient of water which is 18 W/m^2K

So the wattage of heater is 90.47 W
Part b
Now when the probe is above sea water now, the losses are both because of convection and radiation now the loss is given as

Here
- Q_con is the heat loss due to convection which is to be calculated
- A is the area of the body which is given as 0.5026 m^2
- Tbody is 10 C
- Tair is -10C
- h is the convection coefficient of water which is 10 W/m^2K

Radiation loss is given as
Here
- Q_rad is the heat loss due to radiation which is to be calculated
- A is the area of the body which is given as 0.5026 m^2
- Tbody is 10+273=283K
- Tsky is 0+273=273K
- ε is the emissivity of the shell which is 0.85
- τ is the coefficient which is


So the total value of heat loss is

So the wattage of heater is 121.34 W
Answer:
23.98 rpm
Explanation:
d = diameter of merry-go-round = 2.4 m
r = radius of merry-go-round = (0.5) d = (0.5) (2.4) = 1.2 m
m = mass of merry-go-round = 270 kg
I = moment of inertia of merry-go-round
Moment of inertia of merry-go-round is given as
I = (0.5) m r² = (0.5) (270) (1.2)² = 194.4 kgm²
M = mass of john = 34 kg
Moment of inertia of merry-go-round and john together after jump is given as
I' = (0.5) m r² + M r² = 194.4 + (34) (1.2)² = 243.36 kgm²
w = final angular speed
w₀ = initial angular speed of merry-go-round = 20 rpm = 2.093 rad/s
v = speed of john before jump
using conservation of angular momentum
Mvr + I w₀ = I' w
(34) (5) (1.2) + (194.4) (2.093) = (243.36) w
w = 2.51 rad/s
w = 23.98 rpm
Answer:
The velocity
of the cart with respect to the ground is

if we consider North the positive y-direction and East the positive x-direction.
Explanation:
We have for relative motion the following expression:

Where
is the velocity of the cart with respect to the ground,
is the velocity of the cart with respect to the plane and
is the velocity of the plane with respect to the ground.
We find that:


Thus:
Answer:
d. 5.7 x 10⁴ J
Explanation:
I = moment of inertia of the flywheel = 0.525 kg-m²
w₀ = initial angular speed of the flywheel = 69.1 rad/s
w = final angular speed of the flywheel = 471 rad/s
W = work done by the engine on the flywheel
Work done by the engine is given as
W = (0.5) I (w² - w₀²)
Inserting the values
W = (0.5) (0.525) (471² - 69.1²)
W = 5.7 x 10⁴ J