Answer:
The speed of sound, in m/s, through air at this temperature is 343.5 m/s
Explanation:
Given;
distance traveled by sound, d = 1,687.5 meters
time taken for the sound to travel, t = 5 seconds
air temperature, θ = 10°C
Speed of sound = distance traveled by sound / time taken for the sound to travel
Speed of sound = d / t
= 1687.5 m / 5 s
= 337.5 m/s
Speed of sound at the given temperature is calculated as;
c = 337.5 + 0.6θ
c = 337.5 + 0.6 x 10
c = 337.5 + 6
c = 343.5 m/s
Therefore, the speed of sound, in m/s, through air at this temperature is 343.5 m/s
Yes......................
Answer:
a) 17.49 seconds
b) 13.12 seconds
c) 2.99 m/s²
Explanation:
a) Acceleration = a = 1.35 m/s²
Final velocity = v = 85 km/h = 
Initial velocity = u = 0
Equation of motion

Time taken to accelerate to top speed is 17.49 seconds.
b) Acceleration = a = -1.8 m/s²
Initial velocity = u = 23.61\ m/s
Final velocity = v = 0

Time taken to stop the train from top speed is 13.12 seconds
c) Initial velocity = u = 23.61 m/s
Time taken = t = 7.9 s
Final velocity = v = 0

Emergency acceleration is 2.99 m/s² (magnitude)
Answer:
Explanation:
In order to solve this problem we need to make a free body diagram of the book and the forces that interact on it. In the picture below you can see the free body diagram with these forces.
The person holding the book is compressing it with his hands, thus exerting a couple of forces of equal magnitude and opposite direction with value F.
Now the key to solving this problem is to analyze the equilibrium condition (Newton's third law) on the x & y axes.
To find the weight of the book we simply multiply the mass of the book by gravity.
W = m*g
W = 1.3[kg] * 9.81[m/s^2]
W = 12.75 [N]
Answer: The principle of conservation of energy, angular speed and centripetal force
Explanation:
At point A, the car experienced maximum of potential energy
As it moves down the hill, the potential energy decreases while the kinetic energy increases.
The maximum kinetic energy of the car is needed for the attainment of enough centripetal force to help the car move through the loop without falling .