Answer:
v = 12.86 km/h
v = 3.6 m/s
Explanation:
Given,
The distance, d = 13.5 km
The time, t = 21/20 h
= 1.05 h
The velocity of a body is defined as the distance traveled by the time taken.
v = d / t
= 13.5 km / 1.05 h
= 12.86 km/h
The conversion of km/h to m/s
1 km/h = 0.28 m/s
12.86 km/h = 12.86 x 0.28 m/s
= 3.6 m/s
Hence, the velocity in m/s is, v = 3.6 m/s
Answer:
15 protons and 18 electrons
General Formulas and Concepts:
<u>Chemistry</u>
- Reading a Periodic Table
- Element Number
- Neutral Atoms
- Ions
Explanation:
We are given the element P. P is 15 on the Periodic Table, meaning it has 15 protons and 15 electrons (all elements are in neutral form).
P³⁻ ion means the element now has a negative charge of 3. We know protons have a positive charge and electrons have a negative charge. 3- means we will have more electrons than protons.
Therefore, P³⁻ would have 15 protons and <em>18</em> electrons:
15 (+) + 18 (-) = 3 (-)
Answer:
Explanation:
Sam mass=75kg
Height is 50m
20° frictionless slope
Horizontal force on Sam is 200N
According to the work energy theorem, the net work done on Sam will be equal to his change in kinetic energy.
Therefore
Wg - Ww =∆K.E
Note initial the body was at rest at top of the slope.
Then, ∆K.E is K.E(final) - K.E(initial)
K.E Is given as ½mv²
Since initial velocity is zero then, K.E(initial ) is zero
Therefore, ∆K.E=½mVf²
Wg is work done by gravity and it is given by using P.E formulas
Wg=mgh
Wg=75×9.8×50
Wg=36750J
Ww is work done by wind and it's is given by using formulae for work
Work=force × distance
Ww=horizontal force × horizontal distance
Using Trig.
TanX=opposite/adjacent
Tan20=h/x
x=h/tan20
x=50/tan20
x=137.37m
Then,
Ww=F×x
Ww=200×137.37
We=27474J
Now applying the formula
Wg - Ww =∆K.E
36750 - 27474 =½×75×Vf²
9276=37.5Vf²
Vf²=9275/37.5
Vf²= 247.36
Vf=√247.36
Vf=15.73m/s
Answer:
15,00kg
Explanation:
here's your solution
=> force = 45,000N
=> acceleration = 30m/s^2
=> mass = ?
=> Mass = force/acceleration
=> mass = 45,000/30
=> mass = 15,00kg
hope it helps
Answer:
Weight=686.7N, 
, S.G.=0.933, F=17.5N
Explanation:
So, the first value the problem is asking us for is the weight of methanol. (This is supposing there is a mass of methanol of 70kg inside the tank). We can find this by using the formula:
W=mg
so we can substitute the data the problem provided us with to get:
which yields:
W=686.7N
Next, we need to find the density of methanol, which can be found by using the following formula:
we know the volume of methanol is 75L, so we can convert that to 
like this:
so we can now use the density formula to find our the methanol's density, so we get:
Next, we can us these values to find the specific gravity of methanol by using the formula:
when substituting the known values we get:
so:
S.G.=0.933
We can now find the force it takes to accelerate this tank linearly at 
F=ma
F=17.5N
