While pushing a refrigerator up a ramp, there would be less friction to overcome if you used a dolly because of the wheels. So the efficiency of the ramp would be greater with the use of the dolly.
<u>Explanation:</u>
The ramp provides for a wedge setup, so when the refrigerator is being pushed up the ramp, the friction on the ramp would equally distributed to the refrigerator when pushed wholly as the friction applied is a product of the coefficient of friction with the Normal reaction of the weight in contact with the surface.
Therefore, when the dolly is used, the surface in contact becomes divided and thus, the friction applied would become less due to though coefficient of friction remains the same, the normal reaction of the weight becomes small and so does the applied friction. Therefore, efficiency of the ramp increases as the friction is less and work done is more.
Answer:
I = 33.04A
Explanation:
The magnetic field at the center of a loop of wire is proportional to the current flowing through the wire and inversely proportional to the radius
So therefore we have:
20/23 = I/38.0
We then solve for I
cross multiplying we have 20 x 38 = 23 x I
I = 20 x 38/ 23
I = 33.04A
Correct question is;
A ballet dancer spins with 2.4 rev/s with her arms outstretched,when the moment of inertia about axis of rotation is I. With her arms folded,the moment of inertia about the same axis becomes 0.6I about the same axis. Calculate the new rate of spin.
Answer:
4 rev/s
Explanation:
We are given;
Initial Angular velocity; ω_i = 2.4 rev/s
Initial moment of inertia; I_i = I
Final moment of inertia; I_f = 0.6I
From conservation of angular momentum, we have;
I_i × ω_i = I_f × ω_f
Where ω_f is the new rate of spin.
Thus, let's make it the subject to get;
ω_f = (I_i × ω_i/I_f)
Plugging in relevant values, we have;
ω_f = (I × 2.4/0.6I)
I will cancel out to give;
ω_f = 2.4/0.6
ω_f = 4 rev/s
Answer:
elementary particles
Explanation:
Matter is composed of elementary particles i.e. quarks and leptons.
Matter is composed of elementary particles which is called quarks and leptons. Quarks consist of protons, neutrons and electrons. All observable matter is made up of up quarks, down quarks and electrons.
Lepton is an elementary particle consist of half-integer spin that does not undergo strong interactions. Leptons exist on two main classes i.e. charged leptons, and neutral leptons. Electron, electron neutrino, muon, muon neutrino, tau and tau neutrino are the six types of leptons.
The acceleration and velocity of the plane is 78.57 m/s² and 157.14 m/s respectively
To calculate the acceleration of the plane, we use the formula below.
<h3>Formula:</h3>
- a = F/m..................... Equation 1
Where:
- a = Acceleration of the plane
- F = Force applied to the plane
- m = mass of the plane.
From the question,
Given:
Substitute these values into equation 1
- a = 550000/7000
- a = 78.57 m/s²
To calculate the velocity, we use the formula below.
- v = u+at............. Equation 2
Where:
- v = Final velocity
- u = initial velocity
- a = acceleration
- t = time.
From the question,
Given:
- u = 0 m/s
- a = 78.57 m/s
- t = 2.0 seconds
Substitute these values into equation 2
Hence, The acceleration and velocity of the plane is 78.57 m/s² and 157.14 m/s respectively.
Learn more about acceleration here: brainly.com/question/460763
