Work done is given by product of force and displacement due to that force
So here we will have

here we know that


Now work done is given as


so it will do 16 J work to move the box
Answer:
Points downward, and its magnitude is 9.8 m/s^2
Explanation:
The motion of a projectile consists of two independent motions:
- A uniform horizontal motion, with constant velocity and zero acceleration. In fact, there are no forces acting on the projectile along the horizontal direction (if we neglect air resistance), so the acceleration along this direction is zero.
- A vertical motion, with constant acceleration g = 9.8 m/s^2 towards the ground (downward), due to the presence of gravity wich "pulls" the projectile downward.
The total acceleration of the projectile is given by the resultant of the horizontal and vertical components of the acceleration. But we said that the horizontal component is zero, therefore the total acceleration corresponds just to its vertical component, therefore it is a vector with magnitude 9.8 m/s^2 which points downward.
Answer:
The correct answer is 
Explanation:
The formula for the electron drift speed is given as follows,

where n is the number of of electrons per unit m³, q is the charge on an electron and A is the cross-sectional area of the copper wire and I is the current. We see that we already have A , q and I. The only thing left to calculate is the electron density n that is the number of electrons per unit volume.
Using the information provided in the question we can see that the number of moles of copper atoms in a cm³ of volume of the conductor is
. Converting this number to m³ using very elementary unit conversion we get
. If we multiply this number by the Avagardo number which is the number of atoms per mol of any gas , we get the number of atoms per m³ which in this case is equal to the number of electron per m³ because one electron per atom of copper contribute to the current. So we get,

if we convert the area from mm³ to m³ we get
.So now that we have n, we plug in all the values of A ,I ,q and n into the main equation to obtain,

which is our final answer.
The distance D where the object comes to rest is 1.08.m.
<h3>What is the distance?</h3>
- The separation of one thing from another in space; the distance or separation in space between two objects, points, lines, etc.; remoteness. The distance of seven miles cannot be accomplished in one hour of walking.
- Learn how to use the Pythagorean theorem to get the separation between two points using the distance formula. The Pythagorean theorem can be rewritten as d==(((x 2-x 1)2+(y 2-y 1)2)
- The distance between any two places is the length of the line segment separating them. By measuring the length of the line segment that connects the two points in coordinate geometry, the distance between them may be calculated.
(c) the distance D where the object comes to rest.
ΔKE ⇒ -0.25*1*9.8*D = 0-1/2*1*
⇒
⇒1.08.m
To learn more about distance, refer to:
brainly.com/question/4998732
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Answer:
The magnitude of the tension in he string is equal to the magnitude of the weight of the object.
Explanation:
According to the Newton's 1st law, An object will remain at rest or in uniform motion in a straight line unless acted upon by an unbalanced force.
In here, the elevator is moving with a constant speed. So the object must have the equal constant speed. Which means, it has a uniform motion. According to Newton's 1st law, the total unbalanced force on the object must be zero . As we know, there are only two forces are on the object and they are,
The tension in string(T) , The weight of the object(W) .
∴ F = 0
T - W = 0
So to balanced those forces, the magnitude of the tension in the string must be equal to the magnitude of the weight of the object.