The correct answer is - Positive acceleration describes an increase in speed; negative acceleration describes a decrease in speed.
Technically friction is acting on the car because it is still rubbing against the street and gravity is pulling the car down preventing it from floating??? lol
Answer:
a)Distance traveled during the first second = 4.905 m.
b)Final velocity at which the object hits the ground = 38.36 m/s
c)Distance traveled during the last second of motion before hitting the ground = 33.45 m
Explanation:
a) We have equation of motion
S = ut + 0.5at²
Here u = 0, and a = g
S = 0.5gt²
Distance traveled during the first second ( t =1 )
S = 0.5 x 9.81 x 1² = 4.905 m
Distance traveled during the first second = 4.905 m.
b) We have equation of motion
v² = u² + 2as
Here u = 0, s= 75 m and a = g
v² = 0² + 2 x g x 75 = 150 x 9.81
v = 38.36 m/s
Final velocity at which the object hits the ground = 38.36 m/s
c) We have S = 0.5gt²
75 = 0.5 x 9.81 x t²
t = 3.91 s
We need to find distance traveled last second
That is
S = 0.5 x 9.81 x 3.91² - 0.5 x 9.81 x 2.91² = 33.45 m
Distance traveled during the last second of motion before hitting the ground = 33.45 m
1. <span>Molecules rearrange and form new molecules - exchange (they exchange some material in order to produce new things)
2. </span><span>simultaneous decomposition and synthesis - reversible (it can go back)
3. </span><span>bonds broken and elements released - decomposition
4. </span><span>molecules formed from components - synthesis (these components merge and create molecules)</span>