75000 lol enjoy..............using up 20 characters
They can change because the law of conservation of energy allows it to happen, for example when you are sitting, your body is at a potential energy state, meaning you are inert, you are not moving, but when you get up and suddenly start walking or running, that energy is converted to kinetic energy, meaning that you are moving and can be changed back into potential energy if all of a sudden you stop running or walking to rest or sit down. This is just an example of how energy can are transferred multiple ways
W=F*S
W - Work
F - Force
S - Distance (from latin word 'spatium)
so...
S= 5 (m)
W=60 (J)
W=F*S
F=W/S
F=60/5=12 J/m = 12 N (Newtons)
B) lowering the activation energy !
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hope it helps!
Answer:
The speed of the raft is 1.05 m/s
Explanation:
The equation for the position of the stone is as follows:
y = y0 + v0 · t + 1/2 · g · t²
Where:
y = height of the stone at time t
y0 = initial height
v0 = initial speed
t = time
g = acceleration due to gravity
The equation for the position of the raft is as follows:
x = x0 + v · t
Where:
x = position of the raft at time t
x0 = initial position
v = velocity
t = time
To find the speed of the raft, we have to know how much time the raft traveled until the stone reached the river. For that, we can calculate the time of free fall of the stone:
y = y0 + v0 · t + 1/2 · g · t² (v0=0 because the stone is dropped from rest)
If we place the origin of the frame of reference at the river below the bridge:
0 m = 95.6 m - 9.8 m/s² · t²
-95.6 m / -9,8 m/s² = t²
t = 3.12 s
We know that the raft traveled (4.84 m - 1.56 m) 3.28 m in that time, then the velocity of the raft will be:
x/t = v
3.28 m / 3.12 s = v
v = 1.05 m/s