Which direction do all waves travel?

A hand lifts a block vertically upward at constant velocity. The work done by gravity on the block ____ if the system consists o

adelina 88 [10]

Answer:

If the system consists of the block only, the work done by the gravity is negative.

If the system consists of the block and the earth the work done by the gravity is zero.

Explanation:

If the system consists of the block only, then the system experiences two external forces: one exerted by the hand that lifts the block vertically upward and other exerted by the earth (gravity), which is opposed to the movement of the system, so the work done by gravity is negative.

On the other hand, if the system consists of the block and the earth, then only exists a external force which is the exerted by the hand. So, the force exerted by gravity is zero.

6 0

3 years ago

when approaching the front of an idling jet engine, the hazard area extends forward of the engine approximately

Dominik [7]

when approaching the front of an idling jet engine, the hazard area extends forward of the engine approximately 25 feet.

<h3>What impact, if any, would jet fuel and aviation gasoline have on a turbine engine?</h3>

Tetraethyl lead, which is present in gasoline, deposits itself on the turbine blades. Because jet fuel has a higher viscosity than aviation gasoline, it may retain impurities with greater ease.

Once the gasoline charge has been cleared, start the engine manually or with an electric starter while cutting the ignition and using the maximum throttle.

On the final approach, the aeroplane needs to be re-trimmed to account for the altered aerodynamic forces. A substantial nose-down tendency results from the airflow producing less lift on the wings and less downward force on the horizontal stabiliser due to the reduced power and slower velocity.

Learn more about turbine engine refer

brainly.com/question/807662

#SPJ4

7 0

1 year ago

Find the weight of a 25 kg table. (Use g= 10 m/s?)

PtichkaEL [24]

Answer:

weight = 25*10 =250 N

Explanation:

g must be given in units of m/s^2

The weight of any type of body will be the product of his mass by the gravity

where:

m =mass [kg]

F = force [N] or [kg*m/s^2]

g = acceleration [m/s^2]

3 0

3 years ago

Read 2 more answers

A hot air balloon has a volume of 65,00 cubic feet of hot air. The balloon is at sea level on a standard day. If the temperature

seraphim [82]

If you heat that air by 100 degrees F, it weighs about 7 grams less. Therefore, each cubic foot of air contained in a hot air balloon can lift about 7 grams. That's not much, and this is why hot air balloons are so huge -- to lift 1,000 pounds, you need about 65,000 cubic feet of hot air.

6 0

3 years ago

A baseball player friend of yours wants to determine his pitching speed. you have him stand on a ledge and throw the ball horizo

zhenek [66]

Answer:

The pitching speed of your friend is 33.20 m/s

Explanation:

Lets explain how to solve the problem

Your friend throw the ball horizontally that means the vertical initial

component of velocity is zero ( $u_{y}=0$ ).