Answer:
a. P.E = 3430Joules.
b. Workdone = 3430Nm
Explanation:
<u>Given the following data;</u>
Mass = 70kg
Distance = 5m
We know that acceleration due to gravity is equal to 9.8m/s²
To find the potential energy;
Potential energy = mgh
P.E = 70*9.8*5
<em>P.E = 3430J</em>
b. To find the workdone;
Workdone = force * distance
But force = mass * acceleration
Force = 70*9.8
Force = 686 Newton.
Workdone = 686 * 5
<em>Workdone = 3430Nm</em>
Answer:
Time, t = 0.87 seconds
Explanation:
Given that,
Initial velocity of the object, u = 4.3 m/s
The coefficient of kinetic friction between horizontal tabletop and the object is 0.5
We need to find the time taken by the object for the object to come to rest i.e. final velocity will be 0.
Using first equation of motion to find it as :
a is the acceleration, here, 
So, the time taken by the object to come at rest is 0.87 seconds. Hence, this is the required solution.
Answer:
perpendicular
Explanation:
Polaroids are the material that is used to polarize the ray of light. Polaroid consists of microcrystals of herapathite.
When unpolarized light is passed through the Polaroid then ray appears to be of half the intensity and vibration of the ray in the single plane so, the emerged light is known as polarized light
Polaroids are used in the glasses to protect the eye from unwanted rays.
When Light does not pass through a pair of Polaroids then the axis of Polaroids will be perpendicular to the axis of ray.
Try this option, the answers are marked with colour.
