20/40=0.5 g/cm^3 becuase, mass/volume=density.
Just show a picture so I can help ur information is misleading...
Answer:
A. 231.77 J
B. 5330.71 J
C. 46 donuts
Explanation:
A. To lift the barbell once, she will have to extend it the full length of her arm. The work done will then be:
W = F * d
Where the force is the weight of the barbell.
F = m * g
Hence, the work done in lifting the barbell is:
W = m * g * d
W = 43 * 9.8 * 0.55
W = 231.77 J
B. If she does 23 repetitions, the total energy she expend will be equal to the Potential energy when the barbell is lifted multiplied by 23:
E = 23 * m * g * d
E = 23 * 231.77
E = 5330.71 J
C. 1 Joule = 4.184 calories
5330.71 Joules = 5330.71 * 4.184 = 22303.69
If 1 donut contains 490 calories, the number of donuts she will need will be:
N = 22303.69/490 = 45.5 donuts or 46 donuts
Answer:
vector quantities are resolved into their component form (along the x and y-axis) before adding them. Let us assume that two vectors are
→
a
=
x
1
^
i
+
y
1
^
j
and
→
b
=
x
2
^
i
+
y
2
^
j
, we can find the sum of two vectors as follows.
→
a
+
→
b
=
x
1
^
i
+
y
1
^
j
+
x
2
^
i
+
y
2
^
j
=
(
x
1
+
x
2
)
^
i
+
(
y
1
+
y
2
)
^
j
The direction of the sum of the vectors (with positive x-axis) is,
θ
=
tan
−
1
(
y
1
+
y
2
x
1
+
x
2
)
Explanation:
Without the metric system, we'd have a different International System of Units, the metric system is important because 1mm is 0.1cm, 1 cm is 0.01m, with the imperial system the conversion is tedious. The most important feature of the metric system is its base in scientific fact and repeatable standards of measurement
