Answer: 
Explanation:
In the image attached with this answer are shown the given options from which only one is correct.
The correct expression is:

Because, if we derive velocity
with respect to time
we will have acceleration
, hence:

Where
is the mass with units of kilograms (
) and
with units of meter per square seconds
, having as a result 
The other expressions are incorrect, let’s prove it:
This result has units of
This result has units of
This result has units of
and
is a constant
This result has units of
This result has units of
This result has units of
and
is a constant
This result has units of
and
is a constant
because
is a constant in this derivation respect to
This result has units of
and
is a constant
Answer:
884Hz
Explanation:
Beats is the absolute difference between two frequencies therefore
Beats = f1-f2
4=f1-880
F1=880+4
F1=884Hz
Answer: 9130 joules
Explanation:
Workdone by wheelbarrow = ?
Time = 11 seconds
Power = 830 watts
Recall that power is the rate of doing work. Thus, power is workdone divided by time taken.
i.e Power = (workdone/time)
830 watts = Workdone / 11 seconds
Workdone = 830 watts x 11 seconds
Workdone = 9130 joules
Thus, 9130 joules of work is required to get the wheelbarrow across the yard.
Answer:
1.
Firstly removing off one strip and it leaves electrons behind, so the strip becomes positively charged.
2. The roll however is not negatively charged because it is "earthed " by the hand holding it, thus excess negatives repel each other away through the hand.
3.Tearing off the next strip and once more it leaves electrons behind, the new strip is also positively charged and will repel the first strip.
4. Then, tear two strips apart and one will leave electrons behind on the other. Meaning that one strip is positive and the other is negative and they will attract each other.
<em>Iron, and to a lesser degree, steel, can only become magnetised by passing an electrical current through it (an electromagnet). So a steel ship does not become magnetised in the accepted sense during construction. </em>
<span><em>However, any large mass of iron will affect the accuracy of a magnetic compass, causing it to deviate wildly from magnetic North. This problem was encountered when iron ships were first constructed in the mid-19 Century. It was overcome by mounting the compass in a 'binnacle', a housing containing two large soft iron balls either side of the compass itself, which counteracted the effect of the hull and balanced the compass so that it read correctly</em></span>