It is TRUE. The pivot point of a lever is called the fulcrum .
Out of the given options, ‘it is described as a fundamental force and therefore does not depend on other forces’ is the true statement about gravity.
Answer: Option B
<u>Explanation:
</u>
As we all know that there are four fundamental forces existing in the universe- Electromagnetic force, strong forces, weak forces and the gravitational force.
These are the forces that don’t depend on any other physical force to draw a considerable impact on the physical objects. The gravitational force can be defined as,
Where,
G = Gravitational Constant
= Masses of two substances under consideration
R = distance between the two substances.
Looking upon the formula of gravitational force we can easily estimate that the gravitational force relies on the mass of substances and the relative distance between them. There is no factor than the air friction that hinders the gravitational force and that too in a negligible amount.
Answer:
a)- 1.799 rad/sec²
b)- 17.6 x 10ˉ³Nm
Explanation:
ω₀ = 720 rev/min x (1 min/60 sec) x (2π rad / 1 rev) = 24π rad/s
a) Assuming a constant angular acceleration, the formula will be
α = (ωf -ω₀) / t
As final state of the grindstone is at rest, so ωf =0
⇒ α = (0-24π) / 41.9 = - 1.799 rad/sec²
b)Moment of inertia I for a disk about its central axis
I = ½mr²
where m=2kg and radius 'r'= 0.099m
I = ½(2)(0.099²)
I = 9.8 x 10ˉ³ kgm²
Next is to determine the frictional torque exerted on the grindstone, that caused it to stop, applying the rotational equivalent of the Newton's 2nd law:
τ = I α =>(9.8 x 10ˉ³)(- 1.799)
τ = - 17.6 x 10ˉ³Nm
(The negative sign indicates that the frictional torque opposes to the rotation of the grindstone).
Answer:
The correct answer is
b. Feeding yourself with a spoon
Explanation:
There are two categories of motor skills, fine motor skills and gross motor skills
Fine motorskills also known as dexterity is the synchronized use of small muscles like muscles in the wrists, hands and fingers along with the eyes. Fine motor skills are used for tasks like turning pages or using the computer key board that requires coordinated and precise movements. Human dexterity is reflected in the level of complexity of functions controlled by the nervous system.
Example of fine motor skill is Feeding yourself with a spoon while gross motor skill includes climbing to the top of a large hill spoon, running in a race and crawling
