Answer:
Explanation:
a ) In this case A rests on B and both rest on horizontal surface
Both moves together .
Total reaction due to weight of both of them
R = 1.2 + 3.6 = 4.8 N
friction force by horizontal surface = μ R , μ is coefficient of friction .
= .3 x 4.8 = 1.44 N
Force equal to frictional force will be required to put both of them in uniform motion .
b ) If A is held stationary , friction force will arise at both , the upper and lower surface of B .
At upper surface friction force = μ x weight of A
= .3 x 1.2 = .36 N
At lower surface friction force = μ x weight of A +B
= .3 x 4.8
= 1.44
Total frictional force on B
= 1.8 N N .
So 1.8 N force will be required to put B in uniform keeping A stationary.
Answer:
1)
2)
3)
4)
Explanation:
1)
We can use the following equation:
Here, the initial velocity in the y-direction is zero, the final y position is zero and the initial y position is 25 m.
2)
The equation of the motion in the x-direction is:
3)
The velocity in the y-direction of the stone will be:
Now, the velocity in the x-direction is 15 m/s then the velocity will be:
4)
The angle of this velocity is:
Then α=55.92° negative from the x-direction.
I hope it helps you!
I want to say that the answer is B.
Answer:
<em>a. F = 14 N</em>
<em>b. Since the spheres' charges have different signs, the force is attractive</em>
Explanation:
<u>Coulomb's Law
</u>
The electrical force between two charged objects is directly proportional to the product of their charges and inversely proportional to the square of the distance between the two objects.
Written as a formula:
Where:
q1, q2 = the objects' charge
d= The distance between the objects
The spheres A and B have charges of:
The distance is d=15 cm = 0.15 m.
a. The force is now calculated:
F = 14 N
b. The electrostatic force between charges is repulsive if they have like signs, the force between them is attractive if they have opposite signs.
Since the spheres' charges have different signs, the force is attractive