What is the youngest to oldest mesozoic era, precambrian time, cenozoic era, paleozoic era

A ball moves along a table at a constant velocity and then rolls off the edge of the table. The forces that should be included i

Len [333]

Answer:

Gravity

Explanation:

When the ball is falling to the ground, it is already detached from the table, so the table does not exert any force on it.

Gravity is always present, therefore it is acting on the ball (acting downward), so it must be included into the free-body diagram. Apart from that, there are no other forces acting on the ball (if we neglect air resistance, which is negligible, and it is not mentioned in the options given), therefore the only force which has to be included in the diagram is gravity.

3 0

3 years ago

Air enters the diffuser of a jet engine operating at steady state at 18 kPa, 216 K and a velocity of 265 m/s, all data correspon

earnstyle [38]

Answer:

45.44m/s

Explanation:

To solve this problem it is necessary to go back to the concepts related to the first law of thermodynamics,

in which it deepens on the conservation of the Energy.

The first law of Thermodynamics is given by the equation:

$0 = \dot{Q}-\dot{W}+\dot{m}(h_1-h_2)+\dot{m}(\frac{V_1^2-V^2_2}{2})+\dot{m}g(z_1-z_2)$

Where,

$\dot{Q}=$ Heat transfer

$\dot{W} =$ Work

$\dot{m} =$ Flow mass

$V_i =$ Velocity

$h_i =$ Specific Enthalpy

$g =$ Gravity

$z_i =$ Height

From this equation we have that there is not Heat transfer, Work and changes in Height. Then,

Then our equation would be,

$0=\dot{m}(h_1-h_2)+\dot{m}(\frac{V_1^2-V^2_2}{2})$

Solving for $V_2,$

$V_2 = \sqrt{V_1^2+2(h_1-h_2)}$

From the tables of ideal gas (air) at 216K we have,

$h_1 = 209.97+(219.97-209.97)(\frac{216-210}{220-210})$

$h_1 = 215.97kJ/kg$

From the tables at 250K, we have that

$h_2 = 250.05kJ/kg$

The velocity was previously given, then

$V_1 =265m/s$

Replacing in the equation:

$V_2 = \sqrt{265^2+2(215.97-250.05)*10^3}$

$V_2 = 45.44m/s$

Therefore the velocity of the air at the diffuser exit is 45.44m/s

3 0

4 years ago

In what direction does an object move when affected by an unbalanced force

gayaneshka [121]

Answer:

An unbalanced force means that there are more than one forces with different directions or magnitudes affecting the object. In this case, the vector addition of the forces should be done. The vector addition will result a net force. The object will move in the direction of the net force.

8 0

3 years ago

A centrifuge is used to test space pilots. The centrifuge spins with a centripetal acceleration of 3.04g. If the length of the a

uranmaximum [27]

Answer:

$approx.= 25\frac{m}{s}$

Explanation:

Centripetal acceleration (a) is defined as the square of an object's velocity (V^2) divided by the distance of the object from it's point/axis of revolution (r). So:

$a=\frac{V^{2} }{r}$

which allows us to solve for the velocity:

$V=\sqrt{ar}\\ Since: a=3.04g=(3.04)(9.81),r=21;\\V=\sqrt{(3.04)(9.81)(21)} =25.02...$

3 0

4 years ago

If 1 gallon of a liquid weighs 4 pounds how much would one ounce weight (keep in mind that liquid ounces are different than weig

Bas_tet [7]

Answer:

64 ounces

Explanation:

Pound is the unit of mass in the imperial system of units. It is used in the United States. Its calibration is done with the SI unit of mass which is kilogram. 1 lb = 0.45359237 kg

1 gallon = 4 pounds

1 pound = 16 ounces weight

So,

4 pounds = 16 × 4 = 64 ounces weight

So, 1 gallon is equal to 64 ounces weight.

1 gallon = 128 fluid ounces.

3 0

4 years ago