Answer:
C) 10 cm
Explanation:
We shall first calculate the focal length of the mirror.
object distance u = 20 cm ( negative )
Image distance v = 12 cm ( negative )
using mirror formula
1/ v + 1 /u = 1/ f
-1/12 - 1/ 20 =1/ f
f =- 7.5 cm
In the second case
u = - 30 cm
f = - 7.5 cm
i / v + 1 / u = 1 / f
1 / v - 1/30 = - 1/ 7.5
v = -10 cm
Answer is C that is 10 cm
consider the motion of the mass parallel to the incline
v₀ = initial velocity at the bottom of incline = 0 m/s
v = final velocity at the top of incline = 8.00 m/s
a = acceleration
d = displacement = L = length of incline = 15 m
using the equation
v² = v²₀ + 2 a d
8² = 0² + 2 a (15)
64 = 30 a
a = 64/30
a = 2.13 m/s²
F = applied force
from the force diagram, perpendicular to incline , force equation is given as
N = mg Cos30
μ = Coefficient of friction = 0.426
frictional force acting on the mass is given as
f = μ N
f = μ mg Cos30
parallel to incline , force equation is given as
F - f - mg Sin30 = ma
F - μ mg Cos30 - mg Sin30 = ma
inserting the values
F - (0.426 x 40 x 9.8) Cos30 - (40 x 9.8) Sin30 = 40 (2.13)
F = 425.82 N
Answer: B. Allegheny plateau
Explanation: Allegheny plateau is a mountainous region that makes up the northern part of the United States of America, the following states are located on the Allegheny plateau New York, Pennsylvania, West Virginia and Ohio, it is made up of HORIZONTAL SEDIMENTARY BEDROCK at elevated lands. Allegheny plateau is over 40million area is over 40million acres,it has been a site for Erosion and for millions years,through this erosions some areas have been brought low while others are higher following the deposition of materials by the erosion.
6 is the answer I remember the answer from when I took this and it was easy
The answer is a property of density. The higher the density, the higher the pressure at the bottom.
Pressure = mass / Area. So given that the 4 samples occupy the same area at the bottom, the mass is going to be the determining factor. Per given volume, mercury has the largest mass. The answer is A
