B. 60 cm
All parallel light rays are bent through the focal point of a convex lens, so the rays from the flashlight 150 cm above the floor must go through the same point on the principal axis as the rays from the flashlight 120 cm above the floor. The location of the focal point does not change when the position of the object is moved either vertically or horizontally.
Hope this helps !
Answer:
the lowest velocity which a body must have in order to escape the gravitational attraction of a particular planet or other object.
Explanation:
Use direct proportionality: If 1.25 m = 72 N, then 0.55 m = y
0.55 m × 72 = 39.6.
39.6÷1,25 gives you your answer which is 31.68 N.
Answer:
Our estimate not done correctly because the width was unrealistic.
Explanation:
Given that,
Length = 6 m
Width = 0.5 m
We need to calculate the area of rectangular floor
Using formula of area
Where, l = length
w= width
Put the value into the formula
We need to find why this estimate not done correct
Using given data
We can say that,
We assume width was unrealistic.
The length of room is 6 m.
We know that,
So, the length would be 20 feet.
The width of room is 0.5 m.
The width of room would be 1.64 feet.
So, the area will be
Hence, Our estimate not done correctly because the width was unrealistic.
The question is incomplete, the complete question is;
A spherical steel ball bearing has a diameter of 2.540cm at 25.00∘C.
(a) What is its diameter when it's temperature is raised to
100∘C?
(b) What temperature change is required to increase its volume by
1.000% ?
Answer:
a) 2.542 cm
b) 303.03°C
Explanation:
Given;
Diameter of the ball= 2.540cm
Initial temperature= 25.0°C
Final temperature= 100.0°C
Percentage increase in volume = 1.000%
Temperature coefficient of expansion for steel =11.0×10^−6/∘C
d2= d1[1 + α(T2-T1)]
d2= 2.540[1 + 11.0×10^−6(100-25)]
d2= 2.540[1 + 8.25×10^-4]
d2= 2.542 cm
From;
%V ×1/100 = V ×3α ×∆T/ V
Substituting values;
1.000 ×1/100= 3× 11.0×10^−6 × ∆T
∆T= 0.01/3× 11.0×10^−6
∆T= 303.03°C
