Answer:
D. 0.9
Explanation:
Calculating minimum coefficient of static friction, we first resolve the forces (normal and frictional) acting on the vehicle at an angle to the horizontal into their x and y components. After this, we can now substitute the values of x and y components into equation of static friction. Diagrammatic illustration is attached.
Resolving into x component:
∑
------(1)
Resolving into y component:
∑
------(2)
Static frictional force,
μ
------(3)
substituting
from equation (1) and
from equation (2) into equation (3)
μ
μ
μ 
μ 
The angle the vehicles make with the horizontal α = 42°
μ ≥ tan 42°
μ ≥ 0.9
Answer:
Potential difference though which the electron was accelerated is 
Explanation:
Given :
De Broglie wavelength , 
Plank's constant , 
Charge of electron , 
Mass of electron , m=9.11\times 10^{-31}\ kg.
We know , according to de broglie equation :

Now , we know potential energy applied on electron will be equal to its kinetic energy .
Therefore ,

Putting all values in above equation we get ,

Hence , this is the required solution.
Answer: The comet's average distance from the sun is 17.6AU
Explanation:
From Kepler's 3rd Law, P^2=a^3
Where P is period in years
and a is length of semi-major axis or the average distance of the comet to the sun.
Given the orbital period to be 74 years
74^2 =a^3
5476 = a^3
Cube root of 5476 =a
17.626 = a
Approximately a= 17.6 AU
In the circular motion of the hammer, the centripetal force is given by

where m is the mass of the hammer, v its tangential speed and r is the distance from the center of the motion, i.e. the length of the hammer.
Using the data of the problem, we find:
They have different accelerations because of their masses. According to Newton's Second Law, an objects acceleration is inversely proportional to its mass. Therefore the object with the larger mass, in this case the gun, will have a smaller acceleration. In the same way, the less massive object, being the bullet, will have a higher acceleration.
Hope this helps :)