Muscles function only by contracting. This makes it necessary for one end of the muscle to be fixed and the other mobile.
Take the bicep for example.
Its origin is at the shoulder and its two heads connect to the bones of the forearm, the radius and ulna.
Now, had the muscle not been fixed at one end, and contracted, it would pull both our shoulder and forearm together resulting in an ineffective movement. The desired motion is to lift the forearm (proximal and distal movement) which can only be achieved if the bicep is fixed at the shoulder and allowed to move at the forearm.
Answer:
A. the internal energy stays the same
Explanation:
From the first law of thermodynamics, "energy can neither be created nor destroyed but can be transformed from one form to another.
Based on this first law of thermodynamic, the new internal energy of the gas is the same as the internal energy of the original system.
Therefore, when the partition separating the two halves of the box is removed and the system reaches equilibrium again, the internal energy stays the same.
Answer:
In this case, the index of seawater replacement is 1.33, the index of refraction of air is 1, which is why the angle of replacement is less than the incident angle, so the fish seems to be closer
In the opposite case, when the fish looked at the face of the man, the angle of greater reason why it seems to be further away
Explanation:
This exercise can be analyzed with the law of refraction that establishes that a ray of light when passing from one medium to another with a different index makes it deviate from its path,
n₁ sin θ₁ = n₂ sin θ₂
where n₁ and n₂ are the refractive indices of the incident and refracted means and the angles are also for these two means.
In this case, the index of seawater replacement is 1.33, the index of refraction of air is 1, which is why the angle of replacement is less than the incident angle, so the fish seems to be closer
1 sin θ₁ = 1.33 sin θ₂
θ₂ = sin⁻¹ ( 1/1.33 sin θ₁)
In the opposite case, when the fish looked at the face of the man, the angle of greater reason why it seems to be further away
Answer:
0.00066518 Nm
Explanation:
v = Velocity = 1.2 m/s
r = Distance to head = 2.3 cm
= Final angular velocity
= Initial angular velocity = 0
= Angular acceleration
t = Time taken = 2.4 s
Angular speed is given by

From equation of rotational motion

Torque

The torque of the motor is 0.00066518 Nm
Answer:
Time taken by the leaf to displace by 1.0 m distance is
seconds
Explanation:
As we know that initial velocity of the leaf is given as

now the acceleration upwards for the leaf is

The displacement of leaf in upward direction is
d = 1 m
so now we have


seconds