The trains take <u>57.4 s</u> to pass each other.
Two trains A and B move towards each other. Let A move along the positive x axis and B along the negative x axis.
therefore,
The relative velocity of the train A with respect to B is given by,
If the train B is assumed to be at rest, the train A would appear to move towards it with a speed of 170 km/h.
The trains are a distance d = 2.71 km apart.
Since speed is the distance traveled per unit time, the time taken by the trains to cross each other is given by,
Substitute 2.71 km for d and 170 km/h for 
Express the time in seconds.
Thus, the trains cross each other in <u>57.4 s</u>.
Answer: 750Kg
Explanation:
Recall that force is the product of the mass M, of an object moving at a uniform acceleration.
i.e Force = Mass x Acceleration
In this case, Mass = ?
Force = 3.00 x 10^3 N = (3.00 x 1000N)
= 3000N
Uniform acceleration = 4.00m/s^2
Force = Mass x Acceleration
3000N = Mass x 4.00m/s^2
Mass = (3000N/4.00m/s^2)
Mass = 750Kg (The SI unit of mass is kilograms)
Thus, the mass of the car is 750Kg
Answer:
A new substance was formed
Explanation:
According to this question, a shiny and flexible metal called Magnesium (Mg) is burnt in air to produce a white powder that has no shiny or flexible properties, however, has more weight than the magnesium metal itself.
This is possible because a CHEMICAL CHANGE has occured, hence, a new substance has been formed. The formation of a new substance during the burning process (chemical reaction), induced the increase in mass.
