Eight and I don’t know what else to say but for sure 8
In case of an object sitting at rest on another base, there are two equal and opposite forces – Normal force and the gravity.
Answer: Option A
<u>Explanation:
</u>
When an object is placed at rest position on another object, there is a force exerted by the surfaces of the two contact objects. This force is denoted as Normal Force.
When an object such as a box is placed on a shelf, its surface exerts a contact force on the base of the shelf- The Normal force directed upward. Meanwhile, the gravity stays at its action and tries to pull the box towards itself.
Both of these forces however are equal and opposite and therefore, there is zero net force on the box. That's why it remains at rest, holding on Newton's third law.
Answer
given,
mass of the piano = 170 kg
angle of the inclination = 20°
moves with constant velocity hence acceleration = 0 m/s²
neglecting friction
so, force required to pull the piano
F = m g sin θ
F = 170 × 9.81 × sin 20°
F = 570.39 N
so, force required by the man to push the piano is F = 570.39 N
Answer:
0.146 m/s
Explanation:
We can see it in the pic.
That waves travel faster than the wave lenght!