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3 years ago

A force acting on an object does no work if

2 answers:

8 0

If the force is not in the direction of the object’s motion then a <span> force acting on an object does no work
work is done if force is applied on a body and body covers some distance in the direction of the force
W=FS
hope it helps</span>

KIM [24]3 years ago

3 0

Answer: the force is not in the direction of the object’s motion.

Explanation:

Work = Force. Displacement

⇒ W = F. s = F s cos θ

Thus, work is said to be done when a force displaces an object from its position in the direction of the force.

If the force is less the frictional force, the object would not move. An object accelerates when a force is applied. Sometimes, the direction of force and direction of motion is not same. In that case, no work is said to be done.

For example, when porter lifts the weight on head and moves forward. The weight is perpendicular to the direction of motion. cos 90° = 0 ⇒ W = 0

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If I = 2.0 A in the circuit segment shown below, what is the potential difference VB - VA?

Tom [10]

Answer:

10 V

Explanation:

The potential difference between two points is the amount of work required to carry a unit charge from one point to the other point. This would result in a potential difference between this two points.

The difference between the potential across two points B and A is $V_{BA}=V_B-V_A$

From the image attached:

$V_B-V_A=10-10I+20\\\\But\ I = 2A,hence:\\\\V_B-V_A=10-10(2)+20\\\\V_B-V_A=10-20+20\\\\V_B-V_A=10\ V$

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3 years ago

Please help me with my quiz?

alina1380 [7]

The solutions would be :
1. C
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3 years ago

I was driving along at 20 m/s, trying to change a CD and not watching where I was going. When I looked up, I found myself 45 m f

cricket20 [7]

Answer:

$a=4.44\frac{m}{s^2}$

Explanation:

First we have to find the time required for train to travel 60 meters and impact the car, this is an uniform linear motion:

$t=\frac{d}{v}\\\\t=\frac{60m}{30\frac{m}{s}}=2s$

The reaction time of the driver before starting to accelerate was 0.50 seconds. So, remaining time for driver is 1.5 seconds.

Now, we have to calculate the distance traveled for the driver in this 0.5 seconds before he start to accelerate. Again, is an uniform linear motion:

$d=vt\\d=20\frac{m}{s}(0.5s)=10m$

The driver cover 10 meters in this 0.5 seconds. So, the remaining distance to be cover in 1.5 seconds by the driver are 35 meters. We calculate the minimum acceleration required by the car in order to cross the tracks before the train arrive, Since this is an uniformly accelerated motion, we use the following equation:

$d=v_0t+\frac{1}{2}at^2\\a=\frac{2(d-v_0t)}{t^2}\\a=\frac{2(35m-20\frac{m}{s}*1.5s}{(1.5s)^2}\\a=4.44\frac{m}{s^2}$

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3 years ago

Two coffee cups one at 80 degrees c another at 60 degrees c are put into a large cup what is the final temperature of the coffee

8_murik_8 [283]

If you're trying to sum it up, it would be 140 degrees c*, otherwise it would probably be 80 degrees c since its more hotter than 60 degrees

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3 years ago

Wolfgang pauli hypothesized an exclusion principle. This principle says two electrons in an atom cannot have the same what?.

PilotLPTM [1.2K]

No two electrons can have the same set of quantum numbers .

<h3>What is Wolfgang Pauli hypothesized an exclusion principle?</h3>

Pauli made a significant advance when he proposed the notion of adding a fourth quantum number to the three that were previously used to represent the quantum state of an electron. Physically speaking, the first three quantum numbers made sense since they had to do with how the electron moved about the nucleus.

The following rule was developed by Austrian physicist Wolfgang Pauli. The quantum numbers of any two electrons cannot be identical.

To put it another way, no two electrons can be in the same state. The Pauli exclusion principle is the name given to this proposition since it forbids electrons from being in the same state.

to learn more about exclusion principle go to - brainly.com/question/90573

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2 years ago