Answer:
Power = 2.45Kw or 2450 Watts.
Explanation:
<u>Given the following data;</u>
Mass, m = 250kg
Height, h = 2m
Time, t = 2secs
We know that acceleration due to gravity, g is equal to 9.8m/s²
Power can be defined as the energy required to do work per unit time.
Mathematically, it is given by the formula;
But Energy = mgh
Substituting into the equation, we have
Power = 2450 Watts
To convert to kilowatt (Kw), we would divide by 1000
Power = 2450/1000
Power = 2.45Kw.
Therefore, the average power output of the weightlifter is 2.45 Kilowatts.
Yo sup??
we should know that
work done=force*displacement
W=F.s
F=10 N
s=8 m
therefore
W=10*8
=80 N
Hope this helps.
Answer:
(a) r = 1.062·R
= 
(b) r = 
(c) Zero
Explanation:
Here we have escape velocity v
given by
and the maximum height given by
Therefore, when the initial speed is 0.241v we have
v = 
so that;
v² = 
v² = 
is then
Which gives
or
r = 1.062·R
(b) Here we have
Therefore we put 
in the maximum height equation to get
From which we get
r = 1.32·R
(c) The we have the least initial mechanical energy, ME given by
ME = KE - PE
Where the KE = PE required to leave the earth we have
ME = KE - KE = 0
The least initial mechanical energy to leave the earth is zero.
The true statements about magnetic fields and forces will be A,D and E.
<h3>What is a magnet?</h3>
An iron piece,alloy, or other substance with its constituent atoms arranged in such a way that it shows magnetism qualities,
The function of the magnet is attracting other iron-containing objects or aligning itself in a magnetic field.
There are two poles of the magnet;
1. North Pole.
2. South Pole.
The same poles repel each other, while the opposite poles attract each other. In a sense, south-south and north-north repel. While the north-south and the south-north attract each other.
The correct statements are;
(A). The north pole attracts the south pole of a magnet.
(D)Forces caused by magnetic fields are weaker farther from the magnet.
(E)Magnetic forces can act on an object even if the object isn't touching the magnet.
Hence, the true statements about magnetic fields and forces will be A,D and E.
To learn more about the magnet, refer to the link;
brainly.com/question/13026686
#SPJ1
Answer
mass of the block A = 20 Kg
mass of block B = 10 Kg
acceleration of Block A = ?
acceleration of Block B = ?
Assuming the magnitude of force = 124 N
Applying newton's second law
F = 2 T
T = F/2
now, Tension in the string =
T = 124/2 = 62 N
Weight of the block A
W = m₁ g
W = 20 x 9.8 = 196 N
Weight of the block B
W = m₂ g
W = 10 x 9.8
W = 98 N
Weight of blocks is greater than force applied by the pulley so, the blocks will not move.
Hence, acceleration of the block A and B = 0 m/s²
If the Force magnitude is increased to 294 N
T = F/2 = 294/2 = 147 N
Since this Force is less than Weight A acceleration of the block A = 0 m/s².
For Block B
Tension is more than Weight hence block will move
Net Force = 147 - 98 = 49 N
acceleration =
a = 4.9 m/s²
