Answer: 330.88 J
Explanation:
Given
Linear velocity of the ball, v = 17.1 m/s
Distance from the joint, d = 0.47 m
Moment of inertia, I = 0.5 kgm²
The rotational kinetic energy, KE(rot) of an object is given by
KE(rot) = 1/2Iw²
Also, the angular velocity is given
w = v/r
Firstly, we calculate the angular velocity. Since it's needed in calculating the Kinetic Energy
w = v/r
w = 17.1 / 0.47
w = 36.38 rad/s
Now, substituting the value of w, with the already given value of I in the equation, we have
KE(rot) = 1/2Iw²
KE(rot) = 1/2 * 0.5 * 36.38²
KE(rot) = 0.25 * 1323.5
KE(rot) = 330.88 J
Answer:
1.33×10⁻¹⁰ N
Explanation:
F = GMm / r²
where G is the gravitational constant,
M and m are the masses of the objects,
and r is the distance between them.
F = (6.67×10⁻¹¹ N/m²/kg²) (1000 kg) (2000 kg) / (1000 m)²
F = 1.33×10⁻¹⁰ N
1). Take a sample of the substance. The sample should be the largest
possible that will allow it to be be easily handled and the following steps
to be performed with it.
(The density doesn't depend on the size of the sample, and every sample
of the same substance has the same density. But using a larger sample
can improve the accuracy of the measurements you make, and therefore
improve the accuracy of the density you derive for the substance.)
2). Ask or measure the mass of the sample.
3). Ask or measure the volume of the sample.
4). Divide the mass by the volume. Their quotient is the density
of the substance.
Answer:
the correct affirmation is the 3
Explanation:
Let's analyze the problem with Newton's second law before looking at the claims.
X axis parallel to the plane, positive down
F -fr + Wₓ = ma
Y Axis perpendicular to the plane
N -Wy = 0
With trigonometry
Wₓ = W sin θ
Wy = w cos θ
Let's multiply by the displacement along the plane, to relate to the work, which has as expression W = F d
F d -fr d + Wx d = ma d
Push W₁ = Fd
frictional force W₂ = -fr d
gravity W₃ = Wx d
W₁ + W₃ -W₂ = m a d
Analysis affirmations:
R1) false. The work of gravity is the subtraction
R2) false. Each force contributes according to its magnitude
R3) true. In the equation we see that, if the acceleration is zero, W2 = W1 + W3
R4) False. It equals the difference
the correct affirmation is the 3