Answer:
(A) Velocity will be 1.88 m/sec
(b) Force will be 187.45 N
Explanation:
We have given work done = 4780 j
Distance d = 25.5 m
(A) Mass of the truck m = 
We know that kinetic energy is given by

So 
(B) We know that work done is given by
W = Fd
So 
Answer:
ε = 6.617 V
Explanation:
We are given;
Number of turns; N = 40 turns
Diameter;D = 18cm = 0.18m
magnetic field; B = 0.65 T
Time;t = 0.1 s
The formula for the induced electric field(E.M.F) is given by;
ε = |-NAB/t|
A is area
ε is induced electric field
While N,B and t remain as earlier described.
Area = π(d²/4) = π(0.18²/4) = 0.02545
Thus;
ε = |-40 × 0.02545 × 0.65/0.1|
ε = 6.617 V
(we ignore the negative sign because we have to take the absolute value)
Frictional force and Applied force has same “magnitude” and “opposite” direction.
Option: B
<u>Explanation</u>:
When a book is moved horizontally by applying “force” on the book, the frictional force is opposed to the book by the table. Here, this “frictional force” is opposing the book has the same force what we applied on the book but this frictional force and the applied force are opposite in direction. Always the “frictional force” is opposite to the “applied force” which stops the object to move. For example, if a force applied leftward to the object the frictional force is acted on the right side of the object.
When two objects are in contact they experience a "frictional force". This "frictional force" acts opposite to the force applied on to move the object.
Formula for "frictional force" is 
Where,
is coefficient of friction and N is normal force.
Explanation:
It is given that,
Wavelength of red laser light, 
The second order fringe is formed at an angle of, 
For diffraction grating,

, n = 2


The wavelength λ of light that creates a first-order fringe at 22 is given by :




Hence, this is the required solution.
Answer:
comparing the anatomy of organisms
Explanation:
Basically, Rocks are the solid evidence used to date the earth.
Due to the changing in the genetic make up of organisms,the anatomy of organisms is not a reliable evidence to date the earth.