First speed = 20km/h
Time = 3 hours
Distance = 3×20
<h3> = <u>60 km</u></h3>
Second speed = 30km/h
Time = 4 hours
Distance = 4×30
<h3> = <u>120 km</u></h3>
Total distance = 60+120 = <u>180km</u>
Total time = 3+4 =<u> 7 hours</u>
Average speed = 180/7
<h3> = <u>25.71</u><u> </u><u>km</u><u>/</u><u>h</u></h3>
Hope this will help...
Answer:
Explanation:
The motion of Mary along the circular path is a centripetal.
As Mary moves from one edge of the circular platform to the other edge, she is covering a distance which is the radius of the circular path at a velocity.
According to the relationship
w = v/r where
w is the angular velocity
r is the radius
v is the linear velocity
Initially, before Mary starts, her linear speed is zero and her angular velocity is also zero. As she move towards the opposite edge, she is covering a distance of radius r. According to the formula, increase in radius will leads to decrease in her angular velocity and vice versa. As Mary starts moving towards the centre of the circular path, her angular velocity increases, at the centre of the platform, her angular velocity is at maximum at this point. As she moves further from the center to the other edge, her angular velocity decreases due to increase in distance covered across the circular path.
Answer:
m = 1.5 kg
Explanation:
Data:
- Aceleration (a) = 8 m/s²
- Force (F) = 12 N
- Mass (m) = ?
Use formula:
Replace in the formula:
Equate the newtons:
Simplify m/s²:
It divides:
What is the mass of the train?
The mass of the train is <u>1.5 kilograms.</u>
Answer:
Explanation:
The remaining amount of a radioactive isotope is found as the product of the original amount by (1/2) raised to the number of half-lives elapsed. The formla is:
Where M is the remaining amoun, M₀ i s the initial amount, and n is the number of half-lives.
Here, 1/64 of the original carbon-14 remained, meaning that M/M₀ = 1/64.
Then, you can substitute in the equation and solve:
Then, 6 half-lives elapsed since the mastodon died and the remains were dated.
Then, you must multiply 6 by the <em>half-life </em>time:
- 6 × 5730 years = 34,380 years ← answer
Answer:
Work is the energy required to move an object from one point to another. while power is the energy transferred per unit time.
Energy can also be defined as the ability to do work.