The only vertical forces are weight and normal force, and they balance since the surface is horizontal. The horizontal forces are the applied force (uppercase F) in the direction the block slides and the frictional force (lowercase f) in the opposite direction.
Apply Newton's 2nd Law in the horizontal direction:
ΣF = ma
F - f = ma
where f = µmg
F - µmg = ma
F = m(a +µg)
F = (20 kg)(1.4 m/s² + 0.28(9.8 m/s²)
F = 83 N
A.Momentum Equation
m = mass = 75 kg
v = velocity = 18 m/s
P = momentum
Using the momentum equation , momentum is given as
P = mv
P = 75 x 18
P = 1350 kgm/s
Answer:
Explanation:
Work done in lifting the weight once = mgh
= 20 x 9.8 x (1.9+1.7)
= 705.6 J
= 705.6 / 4.2 calorie
= 168 cals
Total energy to be spent = 600 x 10³ cals
No of times weight is required to be lifted
= 600 x 10³ / 168
= 3.57 x 10³ times
Total time to be taken = 2 x 3.57 x 10³
= 7.14 x 10³ s
=119 minutes .
As the scattering angle of the photon increases, the wavelength associated with the photon increases.
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Explanation:</u></h3>
The particle with quantum mechanical property is known as Compton wavelength. The wavelength of a photon increases during collision. When the scattering angle of the photon is 0 degree then the photon's wavelength increases by 0 and when the scattering angle is 180 degree then the wavelength of the photon will become double. This is known as Compton wavelength.
When a photon undergoes collision process, the photo loses its energy and this energy is transferred to the electrons. This causes energy of the photon to decrease and thus the frequency also decreases. Thus, the wavelength of the photon will increase.
Answer: position (x) and time (t)
Explanation:
A body is said to be in motion when its position changes with time with respect to a stationary observer.
Following are the types of motion:
<u>Uniform motion</u>: When equal amount of distance is covered in equal intervals of time.
<u>Non-Uniform motion</u>: When unequal amount of distance is covered in equal intervals of time.
Motion can be of the following types as well:
<u>Rectilinear motion</u>: when object moves in a straight line.
<u>Circular motion</u>: when object moves in a curved path.
<u>Periodic motion</u>: when motion repeats itself in fixed intervals of time.
Thus, in order to define motion, only two variables are required: position and time. Measuring these variables can determine whether the object is in motion or not and the type of motion.
