Answer:
0.71 m/s
Explanation:
We find the time it takes the stone to hit the water.
Using y = ut - 1/2gt² where y = height of bridge, u = initial speed of stone = 0 m/s, g = acceleration due to gravity = -9.8 m/s² (negative since it is directed downwards)and t = time it takes the stone to hit the water surface.
So, substituting the values of the variables into the equation, we have
y = ut - 1/2gt²
82.2 m = (0m/s)t - 1/2( -9.8 m/s²)t²
82.2 m = 0 + (4.9 m/s²)t²
82.2 m = (4.9 m/s²)t²
t² = 82.2 m/4.9 m/s²
t² = 16.78 s²
t = √16.78 s²
t = 4.1 s
This is also the time it takes the raft to move from 5.04 m before the bridge to 2.13 m before the bridge. So, the distance moved by the raft in time t = 4.1 s is 5.04 m - 2.13 m = 2.91 m.
Since speed = distance/time, the raft's speed v = 2.91 m/4.1 s = 0.71 m/s
Answer:
3/4 filled with water
Explanation:
x = Fraction of box filled
g = Acceleration due to gravity = 9.81 m/s²
= Density of water
V = Volume of water
Weight of empty box is equal to the weight of the water displaced
As all the forces are conserved
So, the box starts to sink when the box is 3/4 filled with water
Answer:
c
Explanation:
Green house effect:
Temperature of atmosphere is going to increased continuously, because infrared light absorbed by gas .This increased in temperature atmosphere is called green house effect.
The green houses gases are as follows
,Carbon diaoxide,water vapor ,,Carbon diaoxide ,Methane ,,Carbon diaoxide oxide,CFCs ,ozone.
So the option c is correct.
Body works like a computer whenever there is any problem it warns you and those warnings are termed as symptoms. Of the body doesn't show symptoms we won't be able to detect the problem in our body.
Explanation:
Given that,
A person walks 9.0 km directly east and then turns left and heads directly north for 12.0 km.
We need to find his displacement from the starting position.
We know that,
Displacement = shortest path covered
For direction,
Hence, this is the required solution.
