By Newton's second law, the net vertical force acting on the object is 0, so that
<em>n</em> - <em>w</em> = 0
where <em>n</em> = magnitude of the normal force of the surface pushing up on the object, and <em>w</em> = weight of the object. Hence <em>n</em> = <em>w</em> = <em>mg</em> = 196 N, where <em>m</em> = 20 kg and <em>g</em> = 9.80 m/s².
The force of static friction exerts up to 80 N on the object, since that's the minimum required force needed to get it moving, which means the coefficient of <u>static</u> friction <em>µ</em> is such that
80 N = <em>µ</em> (196 N) → <em>µ</em> = (80 N)/(196 N) ≈ 0.408
Moving at constant speed, there is a kinetic friction force of 40 N opposing the object's motion, so that the coefficient of <u>kinetic</u> friction <em>ν</em> is
40 N = <em>ν</em> (196 N) → <em>ν</em> = (40 N)/(196 N) ≈ 0.204
And so the closest answer is C.
(Note: <em>µ</em> and <em>ν</em> are the Greek letters mu and nu)
Answer:
Wavelength = 10 m
Explanation:
Given:
Speed = 100 m
Frequency = 10 Hz = 10 
To find : Wavelength = ?
We know that the relationship between wavelength λ, frequency f and speed v is given by the equation
v = fλ
Therefore wavelength λ = v/f
= 100 m
/ 10 m
= 10 m
Hence wavelength = 10 m
Answer:
Explanation:
Yes , their displacement may be equal .
Suppose the displacement is AB where A is starting point and B is end point .
The car is covering the distance AB by going from A to B on straight line . On the other hand plane goes from A to C , then from C to D and then from D to B . In this way plane reaches B from A on a different path which is longer than path of the car . In the second case also displacement of plane is AB . In the second case distance covered is longer but displacement is same that is AB .
Answer: Cognitive
Explanation:
Cognition can be defined as the process of obtaining the knowledge and learning through the experience, senses and thought. Many psychologists can have similar experiences of learning the psychological framework of the society or at the individual level. Thus this can be said that the cognitive psychologist may have similar interests.
I think it is electron. Electrons are located outside of the nucleus