The correct answer to the question is 130.4 N.
CALCULATION;
The mass of the bullet is given as m = 28 gram = 0. 028 kg.
The initial velocity of the bullet u = 55 m/s
The final velocity of the bullet v = 18 m/s.
The distance covered by the bullet through the sand bag s = 29 cm.
= 0.29 m
Let the acceleration of the bullet is a .
From equation of kinematics, we know that-

⇒ 


The negative sign is used due to the fact that force is opposing in nature. Its velocity is decreasing with time.
From Newton's second law of motion, we know that net force on a body is equal to the product of mass with acceleration.
Mathematically F = ma.
Hence, the frictional force exerted on the bullet is calculated as -
F = m × a
= 0.028 × (-4656.897) N
= -130.4 N [ANS]
Here, N ( newton) stands for the unit of force.
Newton's law of universal gravitation states that every particle attracts every other particle in the universe with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.
This is mathematically represented as
<u>F= (G X m1 x m2) /r∧2</u>
where F is the force acting between the charged particles
r is the distance between the two charges measured in m
G is the gravitational constant which has a value of <em>6.674×10^-11 Nm^2 kg^-2</em>
m1 and m2 are the masses of the objects measured in Kg
Now if the distance between the is doubled then r becomes 2r. Substituting this in the above formula we get the new Force as
Force (new) = (G X m1 x m2) /(2r)∧2
Thus dividing Force(new)/Force we get
Force(new)/Force = 1/4.
Thus the gravitational force becomes 1/4th of the original value if the distance between the two masses are doubled.
Answer:
Yes, it's possible.
Explanation:
The average velocity is a mean value:
.
during that displacement, it may occur that the acceleration would negative at any time so at that moment if the velocity goes in the same direction with the acceleration, the velocity will be negative, it may take just a few moments and then go positive again. The velocity can also take negative values if for a moment the object was going backward (opposite direction). so the average velocity only means that the major of the velocity was positive.
Answer:
Average acceleration, 
Explanation:
Given that,
Initial velocity, u = 0 km/h
Final velocity, v = 100 km/h = 27.77 m/s
Time, t = 10 s
We need to find the average acceleration of the vehicle. It is given by the change in velocity divided by time. Som,

So, its average acceleration is
.