Given conditions:
height of object = 7.5cmdistance of object from mirror = 14 cmfocus length = -7 cmimage distance = ?
Using mirror formula:
1/(focus length) = 1/(object distance) + 1/(image distance)
or, -1/7 = 1/14 + 1/(image distance)
or, image distance = -4.66cm (the image formed is a virtual image)
Also, magnification of image is:
image height /height of object = - image distance /object distance
or, image height = - image distance / object distance * height of object
or, image height = -(-4.66) / 14 * 7.5 = 2.49 = 3(nearest whole number)
Answer:
Explanation:
same idea as before Liam, first, find the parallel resistance in 35 || 20
(35*20) / (35+20) = 700 / 55 = 12.727272 ohms
now add the 12.727272 + 15 = 27.727272 ohms total resistance
V = IR
10 = I * 27.727272
10 / 27.727272 = I
0.360655 = I
V = IR (again, but across the 15 ohm resistor)
V = 0.360655 * 15
V = 5.4098
Correct answer is D. Earths rotation
The time (t) it will take for the train to reach to Grenoble is the quotient when the distance (d) is divided by the speed (s). That is,
t = d / s
Substituting the known values,
t = 480 km / 180 km/h
t = 2.667 h
Thus, it will take approximately 2.7 h to reach Grenoble. The answer is letter D.
