Answer:
2682
Explanation:
Work done is given by :
Work = Force x distance
= mg x d
So, work done in lifting the box of 23 kg up to my waist of 1 m high is :
W = mg x d
= 23 x 9.18 x 1
= 211.14
Now work done carrying the box horizontally 6 meters across the room is
W = mg x d
= 23 x 9.18 x 6
= 1266.84
Work done in placing the box on the shelf that is 5.7 m above the ground is
W = mg x d
= 23 x 9.18 x 5.7
= 1203.49
So the total work done is = 211.14 + 1266.84 + 1203.49
= 2681.47
= 2682 (rounding off)
Answer:
Work done = 13605.44
Explanation:
Data provided in the question:
For elongation of 2.1 cm (0.021 m) work done by the spring is 3.0 J
The relation between Energy (U) and the elongation (s) is given as:
U = 
................(1)
where,
k is the spring constant
on substituting the valeus in the above equation, we get
3.0 = 
or
k = 13605.44 N/m
now
for the elongation x = 2.1 + 4.1 = 6.2 cm = 0.062 m
using the equation 1, we have
U = 
or
U = 26.149 J
Also,
Work done = change in energy
or
W = 26.149 - 3.0 = 23.149 J
If 50 identical light bulbs are connected in series across
a single power source, then the voltage across each bulb
is ( 1/50 ) of the voltage delivered by the power source.
Answer:
heat energy and nuclear energy
Explanation:
as a resukt of nuclear fusion, the sun produces two types of energy.
1. heat energy
2. nuclear energy
Answer:
A cosmic year is 365.25 days, some times called a side real year and is just the time it takes for us to go round the sun once.
A light year is the distance light travels in a year. Now light travels at about 186,262 miles a Second! Which is not slow by any ones book.
An experiment was conducted just after Christmas a few years ago. Two girls were selected from the audience and went into two phone boxes a few feet apart. They could only hear each other via the phones. The phone call went to a ground station about 200 miles away, then up to a geostationary coms satellite, back to a ground station 1/3 of the way around the world, then repeated, with a third satellite before being sent from another ground station back to London and the other phone box. We the audience could hear both sides of the conversation from both boxes. And could hear the delay between sending and receiving. So even at the speed of light, there was about 1.5 seconds of delay. So because distances in space are so vast that saying a star is x millions of miles away causes problems, you run out of zero’s! So our nearest other star is about 4.5 light years away. Our sun (our nearest start) is about 8 light minuets away. Varies slightly as our orbit is not 100% cirular.
I HOPE THIS IS HELPFUL.
