Explanation:
First, we need to determine the distance traveled by the car in the first 30 minutes, 
.
Notice that the unit measurement for speed, in this case, is km/hr. Thus, a unit conversion of from minutes into hours is required before proceeding with the calculation, as shown below
Now, it is known that the car traveled 40 km for the first 30 minutes. Hence, the remaining distance, 
, in which the driver reduces the speed to 40km/hr is
.
Subsequently, we would also like to know the time taken for the car to reach its destination, denoted by 
.
.
Finally, with all the required values at hand, the average speed of the car for the entire trip is calculated as the ratio of the change in distance over the change in time.
Therefore, the average speed of the car is 50 km/hr.
Answer:
the second one!
Explanation:
the question is well, the question, a hypothesis is an educated guess on what you think will be the outcome
Answer:
1.33×10⁻¹⁰ N
Explanation:
F = GMm / r²
where G is the gravitational constant,
M and m are the masses of the objects,
and r is the distance between them.
F = (6.67×10⁻¹¹ N/m²/kg²) (1000 kg) (2000 kg) / (1000 m)²
F = 1.33×10⁻¹⁰ N
''Energy is destroyed because animals are higher levels do not need as much energy'' is not the valid reason.
<h3>What is respiration?</h3>
Respiration is the cellular process of releasing energy from food. Some of the energy released is used to produce ATP. 90 percent of energy is lost as heat energy whereas 10 percent energy is transferred to other trophic levels.
So we can conclude that ''Energy is destroyed because animals are higher levels do not need as much energy'' is not the valid reason.
Learn more about energy here: brainly.com/question/19666326
Answer:
acceleration = 45 m/s²
Time = 20 seconds
Explanation:
We are given;
Distance; s = 90m
Final velocity;v = 90 m/s
Since shot from rest, initial velocity;u = 0 m/s
So, to find the acceleration, we can use Newton's 2nd law of motion which is;
v² = u² + 2as
Where a is acceleration
Plugging in the values;
90² = 0² + 2a(90)
8100 = 180a
a = 8100/180
a = 45 m/s²
Now, for the time, we will use Newton's 1st law of motion which is;
v = u + at
Where t is time;
So;
90 = 0 + 4.5t
90 = 4.5t
t = 90/4.5
t = 20 seconds
