Answer:
a) Focal length of the lens is 8 cm which is a convex lens
b) 6 cm
c) The lens is a convex lens and produces a virtual image which is upright and two times larger than the object.
Explanation:
u = Object distance = 4 cm
v = Image distance = -8 cm
f = Focal length
Lens Equation

a) Focal length of the lens is 8 cm which is a convex lens
Magnification

b) Height of image is 2×3 = 6 cm
Since magnification is positive the image upright
c) The lens is a convex lens and produces a virtual image which is upright and two times larger than the object.
Answer and Explanation:
A. We have temperature t = 32
Speed of sound, s = 1087.5
As t increases by 1⁰f speed increases by 1.2
So that
S = 1088.6
T= 33⁰f
We have 2 equations
1087.5 = k(32) + c
1088.6 = k(33) + c
Subtracting both equations
(33-32)k = 1088.6-1087.5
K = 1.1
b.). S = kT + c
1087.5 = 32(1.1) + c
Such that
C = 1052.3
Therefore
S = 1.1(t) + 1052.3
C.). S = 1.1t + 1052.3
We make t subject of the formula
T = s/1.1 - 1052.3/1.1
T = 0.90(s) - 956.3
D. This means that We have temperature to rise by 0.90 whenever speed is increased
<span><u>Answer
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The mass of 220 lb football has less than 288 lb football. So, it will be easier to move it since it will require less force. The heavy football will have a bigger momentum. Since 288 lb has more weight than 220 lb, it will have bigger inertia making it difficult for the players to stop it.
This makes it easier to tackle 220 lb football than 288 lb football.
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<span>Answer:The weight of the door creates a CCW torque given by
Tccw = 145 N*3.13 m / 2
You need a CW torque that's equal to that
Tcw = F*2.5 m*sin20</span>
If you did this then it could lead to cheating or someone else getting hurt.