Answer:
a) 1.55 cm
b) 4.25 cm
Explanation:
Given:
Distance between an object and the image = 5.80 cm
Focal length of the lens, f = -2.60 cm
let the image distance be 'v' and the object distance be 'u'
thus,
u + v = 5.80 cm
or
u = 5.80 - v
from the lens formula, we have
on substituting the values, we have
on rearranging, we get
-3.84 × (v × (5.80 - v)) = v + 5.80 - v
or
-2.23v + 3.84v² = 5.80
or
3.84v² - 2.23v - 5.80 = 0
on solving the quadratic equation, we get
v = 1.55 cm
and u = 5.80 - 1.55 = 4.25 cm
hence,
a) 1.55 cm
b) 4.25 cm
Answer:
Average power output of athlete = 11025 Watts
Explanation:
Work done is defined as the product of force applied and the displacement perpendicular to the force.
Work = 
Power is defined as work done per unit time.
Power = 
Here the person lifts 900 kg.
Height = 2.5 m
Time interval = 2 seconds
Force = 
= 
= 8820 N
Work done =
= 
= 22050 J
Power = 
= 11025 Watt
Answer:
the weight of the ball is w = 51.94 N ( mass = 5.3 kg)
Explanation:
Following Newton's second law:
net force = mass * acceleration = weight/gravity * acceleration
then denoting 1 and 2 as the first and second lift
F₁ - w= w/g *a₁
F₂ -w = w/g *a₂ = w/g * 2.07a
dividing both equations
(F₂- w)/(F₁ -w)= 2.07
(F₂- w) = 2.07 * (F₁ -w)
1.07*w = 2.07*F₁ - F₂
w = (2.07*F₁ - F₂ )/ 1.07
replacing values
w = (2.07*61.1 N - 70.9 N )/ 1.07 = 51.94 N
then the weight of the ball is w = 51.94 N ( mass = 5.3 kg)
Answer:
Current, I = 0.0011 A
Explanation:
It is given that,
Diameter of rod, d = 2.56 cm
Radius of rod, r = 1.28 cm = 0.0128 m
The resistivity of the pure silicon, 
Length of rod, l = 20 cm = 0.2 m
Voltage, 
The resistivity of the rod is given by :
R = 893692.30 ohms
Current flowing in the rod is calculated using Ohm's law as :
V = I R
I = 0.0011 A
So, the current flowing in the rod is 0.0011 A. Hence, this is the required solution.
Explanation:
If box weight 25N on ground
MA=F
M(10)=25
M=2.5Kg
