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.
Alfred Wegener first presented his hypothesis to the German Geological Society on 6 January 1912. His hypothesis was that the continents had once formed a single landmass, called Pangaea, before breaking apart and drifting to their present locations.
Answer:
Centripetal acceleration will be equal to
Explanation:
We have given time taken to cover 180° is 0.5 sec
So time taken by 360° is equal to = 2×0.5 = 1 sec
Radius of the circle r = 0.520 m
So distance 
So velocity 
We have to find the centripetal acceleration
Centripetal acceleration will be equal to 
So centripetal acceleration will be equal to
Answer:
-730KJ
Explanation:
According to the first law of thermodynamics;
Let the total energy of the system be ∆E
Let heat be q and let work the w
Since the energy decreases ∆E is negative
Since work is done on the system w= positive
So;
- 250 = 480 + q
q = -250 - 480
q=-730KJ