If an object suspended by a scale shows a weight of 3 N in air, and 2 N when submerged in water, the buoyant force on the submer
1 answer:
You might be interested in
Answer:
In the vertical direction the acting forces are the normal force and the weight of the bobsleder plus the sled. In the horizontal direction the acting force is the friciton force.
Explanation:
Hi there!
Please, see the attached figure for a graphic representation of the forces acting on the sled after the bobsleder jumped in.
In the vertical direction, the acting forces are the normal force (N) and the weight of the sled plus the bobsledder (W).
Since the sled is not being accelerated in the vertical direction, the sum of forces in that direction is zero:
∑Fy = W + N = 0 ⇒ W = N
The weight is calculated as follows:
W = (mb + ms) · g
Where:
mb = mass of the bobsleder.
ms = mass of the sled.
g = acceleration due to gravity.
In the horizontal direction the only acting force is the friction force (Fr). The friction force is calculated a follows:
Fr = N · μ
Where:
N = normal force.
μ = kinetic friction coefficient.
Since N = W = (mb + ms) · g
Fr = (mb + ms) · g · μ
If we want to find the acceleration of the sled after the bobsleder jumps in, we can apply Newton's second law:
∑F = m · a
Where "a" is the acceleration and "m" is the mass of the object (in this case, the mass of bobsleder plus the mass of the sled).
∑F = Fr = (mb + ms) · g · μ = (mb + ms) · a
(mb + ms) · g · μ = (mb + ms) · a
Solving for "a":
g · μ = a
Answer:
Energy stored, U = 66.6 J
Explanation:
It is given that,
Number of turns in the solenoid, n = 500
Radius of solenoid, r = 1.5 cm = 0.015 m
Distance, d = 15 cm = 0.15 m
Let U is the energy stored in the solenoid. Its formula is given by :
L is the self inductance of the solenoid
N is the no of turns per unit length
L = 0.00148 Henry
U = 66.6 J
Out of given options, the correct option for the energy stored in the solenoid is 70 J. So, the correct option is (a) "70 J".
<h2>Option A is the correct answer.</h2>
Explanation:
When an elevator moves upward with consonant acceleration a, the overall acceleration on the body is given by
a' = a + g
So acceleration of pendulum is a + g.
We have equation for period of simple pendulum
In normal case a' = g here a' is more.
From the equation we can see that period of simple pendulum is inversely proportional to square root of acceleration.
Since acceleration increases period decreases.
Option A is the correct answer.