Answer:
v = 46.67 km/h
Explanation:
We will use the following formula throughout this numerical:
s = vt
where,
s = distance covered
v = speed
t = time taken
<u>FOR FIRST 30 km:</u>
s = 30 km
v = 30 km/h
t = t₃₀ = ?
Therefore,
30 km = (30 km/h)(t₃₀)
t₃₀ = (30 km)/(30 km/h)
t₃₀ = 1 h
<u>FOR TOTAL 100 km:</u>
s = 100 km
v = 40 km/h (Average Speed)
t = total time = ?
Therefore,
100 km = (40 km/h)(t)
t = (100 km)/(40 km/h)
t = 2.5 h
<u>FOR LAST 70 km:</u>
s = 70 km
t₇₀ = t - t₃₀ = 2.5 h - 1 h = 1.5 h
v = v₇₀ = ?
Therefore,
70 km = v(1.5 h)
v = 70 km/1.5 h
<u>v = 46.67 km/h</u>
The indicated features of how the painting represents the milky way galaxy include the following:
<h3>What is Milky way?</h3>
This is the galaxy which comprises of our solar system and has a milky appearance when it's viewed from the earth.
The painting represented it as a result of the spiral arm and other features which are listed above.
Read more about Milky way here brainly.com/question/13956361
Gravitational force is determined by mass
Answer: Option B
<u>Explanation:</u>
According to Universal law of gravity, the gravitational force is directly proportional to the product of the masses of the objects and inversely proportional to the square of the distance between the objects.
Where,
G – gravitational constant =
= masses of two objects
r – distance between the objects
So, as per this law, the gravitational force is found by mass.
Answer: 20580 Joules of work is done by the firefighter.
Explanation:
Work done is defined as the force times distance travelled.
work=
Given:
mass= 75 kg
acceleration due to gravity =
h= height = 28 m
Putting in the values we get,
work=
Thus 20580 Joules of work is done by the firefighter.