Answer:
Explanation:
<u>Motion with Constant Acceleration</u>
A body moves with constant acceleration when the speed changes uniformly in time. The equation used to find the final speed vf is
Where vo is the initial speed, a is the acceleration, and t is the time.
The cyclist has an initial speed of vo=10 miles/hour and ends up at vf=20 miles/hour in t=5 seconds.
Both speeds are given in miles/hour and we must convert it to m/s:
1 mile/hour = 0.44704 m/s
10 mile/hour = 4.47 m/s
20 mile/hour = 8.94 m/s
The acceleration is calculated by solving for a:
T = 3.5 secs
Velocity (v) = g * t = 10 m/s^2 * 3.5 sec = 35 m/s
Answer:
Explanation:
Given
Weight of Person 
Cave is 
deep
Breaking stress 
Net Force on Person
The shortest time such that the person can be taken out of cave
where
h=distance moved
t=time
a=acceleration
Question 18: a
question 19: b
question 20: c
Answer:
The amount of energy required is 
Explanation:
The energy required to convert the ice to steam is the sum of:
1) Energy required to raise the temperature of the ice from -20 to 0 degree Celsius.
2) Latent heat required to convert the ice into water.
3) Energy required to raise the temperature of water from 0 degrees to 100 degrees
4) Latent heat required to convert the water at 100 degrees to steam.
The amount of energy required in each process is as under
1) 
where
' is specific heat of ice =
2) Amount of heat required in phase 2 equals
3) The amount of heat required to raise the temperature of water from 0 to 100 degrees centigrade equals
where
' is specific heat of water=
4) Amount of heat required in phase 4 equals
Thus the total heat required equals 
