Answer:
1. the pencil would have the momentum and would keep going until it hits the windshield. 2. when the car suddenly accelerates, the pencil would be inert and it would move toward the back of the car until a constant speed from the car is reached.
Answer:

Explanation:
As we know that if the object is placed on the inclined plane then the force of friction on the object is counterbalanced by the component of the weight of the object along the inclined plane.
So we can say

now if we increase the inclination of the plane then the component of the weight weight along the inclined plane will increase and hence the friction force will also increase.
As we know that the limiting value or the maximum value of friction force at the static condition is given by


so we have

so we will have

so now we have

so maximum possible angle of the inclined plane is

Answer:

Explanation:
Average velocity of oxygen molecule at given temperature is

now we have
M = 32 g/mol = 0.032 kg/mol
T = 27 degree C = 300 K
now we have


now for de Broglie wavelength we know that



To do this you want to solve for one variable at a time. So we want to cancel out a variable. Lets cancel x. I will multiply the first equation by the number 4 to get 4y=4x-16.
Now lets solve equation 2 for y, giving
-3y=-4x+3 now add equation 1 to equation 2
Y =-13
Now plug that back in to either
-13=x-4
X=-9
So the answer is (-9,-13)