Answer:
40 N
Explanation:
We are given that
Speed of system is constant
Therefore, acceleration=a=0
Tension applied on block B=T=50 N
Friction force=f=10 N
We have to find the friction force acting on block A.
Let T' be the tension in string connecting block A and block B and friction force on block A be f'.
For Block B

Where
=Mass of block B
Substitute the values


For block A

Where
Mass of block A
Substitute the values


Hence, the friction force acting on block A=40 N
Answer:
The speed at the bottom of the driveway is3.67m/s.
Explanation:
Height,h= 5sin20°= 1.71m
Potential energy PE=mgh= 2000×9.8×1.71
PE= 33516J
KE= PE- Fk ×d
0.5mv^2= 33516 - (4000×5)
0.5×2000v^2= 33516 - 20000
1000v^2= 13516
v^2= 13516/1000
v =sqrt 13.516
v =3.67m/s
So we want to know what will happen if we put a magnetically soft material in a strong magnetic field. A magnetically soft material is a material whose magnetic field can easily be reversed. Those are ferromagnetic materials. Iron is such a material. When a magnetically soft material is placed into a strong magnetic field it gets its own magnetic field. But its not a permanent magnetic field, it can be changed by a different strong magnetic field.
Mechanical energy is the answer
Dispersion occurs due to the different degrees of refraction experienced by different colours of light. Light of different colours may travel with the same speed in a vacuum, but they travel at different speeds in some refracting medium. The speed of violet light is relatively lower than that of red light.