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
Answer:
d) 1/32 microgram
Explanation:
First half life is the time at which the concentration of the reactant reduced to half.
Second half reaction is the time at which the remaining concentration reduced to half or the initial concentration reduced to 1/4.
Third half life is the time at which the remaining concentration reduced to half or the initial concentration reduced to 1/8.
Forth half life is the time at which the remaining concentration reduced to half or the initial concentration reduced to 1/16.
Fifth half life is the time at which the remaining concentration reduced to half or the initial concentration reduced to 1/32.
The initial mass of the sample = 1 microgram
After 5 half-lives, the mass should reduce to 1/32 of the original.
So the concentration left = 1/32 of 1 microgram = 1/32 microgram
Answer: iron, nickel, and cobalt.
Explanation:
Answer:
<h2>2500 N</h2>
Explanation:
The weight of the object can be found by using the formula
w is the workdone
d is the distance
From the question we have
We have the final answer as
<h3>2500 N</h3>
Hope this helps you
Answer:
The amount of time needed for this heating to occur is 126.25 min
Explanation:
Given;
power required to heat the room = 2kW
volume of the room = 5 m X 5 m X 6 m = 150 m³
atmospheric pressure at sea level = 101 Kpa
Internal energy available in this room, E = PV
= 101 Kpa*150m³
= 15,150 Kpa.m³ = 15,150 KJ
P*t = E
where;
t is the time required to heat this room
1 kW = 3600 kJ/h
2 kW = 7200 kJ/h
Therefore, the amount of time needed for this heating to occur is 126.25 min