Answer:
The carrier lengthen is 0.08436 m.
Explanation:
Given that,
Length = 370 m
Initial temperature = 2.0°C
Final temperature = 21°C
We need to calculate the change temperature
Using formula of change of temperature
We need to calculate the carrier lengthen
Using formula of length
Put the value into the formula
Hence, The carrier lengthen is 0.08436 m.
Answer:
13.78 m/s
Explanation:
Given that:
The mass of the girl & her bicycle = 42 kg
The speed at the top of the hilll= 4 m/s
The height of the hill = 14.3 m
The length of the hill (distance) = 112 m
The frictional force = 20 N
To find the speed at the bottom of the hill; we need to carry out the following processes.
The workdone by gravity = mass × acceleration due to gravity × Δh
= 42 × 9.8 × ( 14.3 - 0 )
= 5885.88 joules
The workdone by the friction = Force × distance = - 20 × 112 (since she is riding down the hill)
The workdone by the friction = -2240 Joules
The initial Kinetic friction = 1/2 mv²
= 1/2 × 42 × 4²
= 336 Joules
The final kinetic energy = Initial Kinetic energy + total work
The final kinetic energy = (336 + 5885.88 - 2240) Joules
The final kinetic energy = 3981.88 Joules
Using the final kinetic energy = 1/2 mv²
3981.88 = 1/2 × 42 × v²
3981.88 = 21 v²
v² = 3981.88/21
v² =189.61
v =
v = 13.78 m/s
Therefore, the speed at the bottom = 13.78 m/s
Hello!!
For this, we only need frequency and speed, so for calculate we applicate formula: