Answer:
Explanation:
Given that,
A lady falling has a final velocity of 4m/s
v = 4m/s
Mass of the lady is 60kg.
m = 60kg
Using conservation of energy, the potential energy of the body from the point where the lady is dropping is converted to the final kinetic energy of the lady.
Therefore,
P.E = K.E(final) = ½mv²
P.E = ½ × 60 × 4²
P.E = 480 J.
Answer:
The magnitudes of the net magnetic fields at points A and B is 2.66 x
T
Explanation:
Given information :
The current of each wires, I = 4.7 A
dH = 0.19 m
dV = 0.41 m
The magnetic of straight-current wire :
B= μ
I/2πr
where
B = magnetic field (T)
μ
= 1.26 x
(N/
)
I = Current (A)
r = radius (m)
the magnetic field at points A and B is the same because both of wires have the same distance. Based on the right-hand rule, the net magnetic field of A and B is canceled each other (or substracted). Thus,
BH = μ
I/2πr
= (1.26 x
)(4.7)/(2π)(0.19)
= 4.96 x
T
BV = μ
I/2πr
= (1.26 x
)(4.7)/(2π)(0.41)
= 2.3 x
T
hence,
the net magnetic field = BH - BV
= 4.96 x
- 2.3 x 
= 2.66 x
T
Answer: most effective way is to practice reduce reuse and recycle for utilisation of resources
Answer:
To calculate anything - speed, acceleration, all that - we need <em>data</em>. The more data we have, and the more accurate that data is, the more accurate our calculations will be. To collect that data, we need to <em>measure </em>it somehow. To measure anything, we need tools and a method. Speed is a measure of distance over time, so we'll need tools for measuring <em>time </em>and <em>distance</em>, and a method for measuring each.
Conveniently, the lamp posts in this problem are equally spaced, and we can treat that spacing as our measuring stick. To measure speed, we'll need to bring time in somehow too, and that's where the stopwatch comes in. A good method might go like this:
- Press start on the stopwatch right as you pass a lamp post
- Each time you pass another lamp post, press the lap button on the stopwatch
- Press stop after however many lamp posts you'd like, making sure to hit stop right as you pass the last lamp post
- Record your data
- Calculate the time intervals for passing each lamp post using the lap data
- Calculate the average of all those invervals and divide by 40 m - this will give you an approximate average speed
Of course, you'll never find an *exact* amount, but the more data points you have, the better your approximation will become.