Answer:
measure the position every so often with a stopwatch
Explanation:
A possible method of measurement is to place a measuring tape along the path and measure the position every so often with a stopwatch, with this we can make a graph of position against time and by extrapolation find the initial velocity.
This is a method used in measurements of uniform movements of bodies
Answer: d= 0.57* l
Explanation:
We need to check that before ladder slips the length of ladder the painter can climb.
So we need to satisfy the equilibrium conditions.
So for ∑Fx=0, ∑Fy=0 and ∑M=0
We have,
At the base of ladder, two components N₁ acting vertical and f₁ acting horizontal
At the top of ladder, N₂ acting horizontal
And Between somewhere we have the weight of painter acting downward equal to= mg
So, we have N₁=mg
and also mg*d*cosФ= N₂*l*sin∅
So,
d=
* tan∅
Also, we have f₁=N₂
As f₁= чN₁
So f₁= 0.357 * 69.1 * 9.8
f₁= 241.75
Putting in d equation, we have
d= 
* tan 58
d= 0.57* l
So painter can be along the 57% of length before the ladder begins to slip
The answer to the question is friction
Answer:
a)W= 1 J
b)W= 1 J
c)W= 0 J
Explanation:
Given that
m = 5 kg
Coefficient of kinetic friction,K=0.5
d= 10 cm
We know that if velocity is constant it means that the acceleration of the system is zero.Or we can say that all forces are balance in the system.
We know that work is the dot product of force and displacement
W= F.d
The friction force on the box
Fr= K m g
Fr= 0.5 x 5 x 10 = 25 N ( take g =10 m/s²)
Fr=25 N
a)
Acceleration a= 0
So horizontal force F = Fr
W = Fr.d
W=10 x 0.1 J
W= 1 J
b)
The work done by friction force
W= 1 J
c)
The net force on the system is zero because acceleration is zero.
F= 0
So
W= 0 J
<h3>
<u>Option</u><u> </u><u>A</u><u>:</u><u> </u><u>1</u><u>9</u><u>.</u><u>5</u><u> </u><u>W</u></h3>
Power of TV = 65Watt
If Efficiency = 70%, then the percentage of energy wasted is 30%
So, the amount of energy getting wasted:
= 30/100 × 65
= 1950/100
= 195/10
= 19.5 W
