Answer:
Friction always acts in the direction opposing motion. This means if friction is present, it counteracts and cancels some of the force causing the motion (if the object is being accelerated).
Explanation:
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other.
<h2>First stage of sleep Deprivation Subject </h2>
During the first stage of sleep deprivation, the subject is NREM which stands for non-rapid eye movement. In this condition, we are not sleeping in the depth. It can be said as dreamless sleep. On electro-encephalography recording, the brain waves are not fast so they have high voltage.
In this condition, the breathing, heart rate and blood pressure is low. The sleep is comparatively tranquil. NREM lasts for 90 minutes to 120 minutes. It accounts for about 75% of the normal sleep time. Rapid eye movements do not occur.
Answer:
Explanation:
Answer:
Explanation:
Given that,
System of two particle
Ball A has mass
Ma = m
Ball A is moving to the right (positive x axis) with velocity of
Va = 2v •i
Ball B has a mass
Mb = 3m
Ball B is moving to left (negative x axis) with a velocity of
Vb = -v •i
Velocity of centre of mass Vcm?
Velocity of centre of mass can be calculated using
Vcm = 1/M ΣMi•Vi
Where M is sum of mass
M = M1 + M2 + M3 +...
Therefore,
Vcm=[1/(Ma + Mb)] × (Ma•Va +Mb•Vb
Rearranging for better understanding
Vcm = (Ma•Va + Mb•Vb) / ( Ma + Mb)
Vcm = (m•2v + 3m•-v) / (m + 3m)
Vcm = (2mv — 3mv) / 4m
Vcm = —mv / 4m
Vcm = —v / 4
Vcm = —¼V •i
