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2 years ago

For work to be accomplished we must have

2 answers:

8 0

The answer they are looking for is the last one. However the last two are technically correct but the third one would result in negative work.

Sunny_sXe [5.5K]2 years ago

8 0

Answer:

a force and a movement in the same direction as the force.

Explanation:

As we know that the formula to find the work done is given by

$W = \vec F. \vec d$

here if the force is applied at some angle with displacement then in that case

$W = F d cos\theta$

now we know that if the force and displacement is in opposite direction then the work done is negative while if the force and displacement is in same direction then the work done is positive

So work to be accomplished only when the sign of the work done is positive so it must be in the same direction as that of displacement of the object

so correct answer would be

a force and a movement in the same direction as the force.

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How are the electric field lines around a positive charge affected when a second positive charge is near it?

Liono4ka [1.6K]

Answer:Because it likes to repel and attract opposites

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3 years ago

A ferry approaches shore, moving north with a speed of 6.2 m/s relative to the dock. A person on the ferry walks from one side o

jasenka [17]

Speed of Ferry is towards North with magnitude 6.2 m/s

Here if we assume that North direction is along Y axis and East is along X axis then we can say

$\vec v_f = 6.2 \hat j$

Now a person walk on ferry with speed 1.5 m/s towards east with respect to Ferry

so it is given as

$\vec v_{pf} = 1.5 \hat i$

also by the concept of relative motion we know that

$\vec v_{pf} = \vec v_p - \vec v_f$

now plug in all values in it

$1.5 \hat i = \vec v_p - 6.2 \hat j$

$\vec v_p = 1.5 \hat i + 6.2 \hat j$

now if we need to find the speed of the person then we need to find its magnitude

so it is given as

$v = \sqrt{1.5^2 + 6.2^2}$

$v = 6.37 m/s$

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3 years ago

When the object is at half its amplitude from equilibrium, is the magnitude of its acceleration at half its maximum value?

Nezavi [6.7K]

We have F = kx or ma = kx where m and k are constants. Therefore, if x is halved, a must be halved too.

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3 years ago

A bee wants to fly to a flower located due North of the hive on a windy day. The wind blows from East to West at speed 6.68 m/s.

Aleonysh [2.5K]

Answer: $53.31\°$ East of North

Explanation:

We have the following data:

Speed of the wind from East to West: $6.68 m/s$

Speed of the bee relative to the air: $8.33 m/s$

If we graph these speeds (which in fact are velocities because are vectors) in a vector diagram, we will have a right triangle in which the airspeed of the bee (its speed relative to te air) is the hypotense and the two sides of the triangle will be the <u>Speed of the wind from East to West</u> (in the horintal part) and the <u>speed due North relative to the ground</u> (in the vertical part).

Now, we need to find the direction the bee should fly directly to the flower (due North):

$sin \theta=\frac{Windspeed-from-East-to-West}{Speed-bee-relative-to-air}$