Answer:
0.29713 m/s
Explanation:
m = Mass of person
g = Acceleration due to gravity = 9.81 m/s²
v = Velocity
r = Radius = 18 mm
By balancing the forces in the system we have
The velocity of the coaster is 0.29713 m/s
How much heat is needed to change the temperature of 3 grams of gold (c = 0.129 ) from 21°C to 363°C? The answer is expressed to
2 answers:
The correct answer to the question is : B) 132 Joules.
EXPLANATION :
As per the question, the mass of the gold m = 3 gram.
The initial temperature of the gold T = 21 degree celsius.
The final temperature of the gold T' = 363 degree celsius.
Hence, the change in temperature dT = T' - T
= 363 - 21 degree celsius
= 342 degree celsius.
The specific heat of the gold is given as c =
We are asked to calculate the heat required ( dQ ) to raise the temperature of gold.
The heat required for this is calculated as -
dQ = mcDT
= 3 × 342 × 0.129 J
= 132.354 J
≈ 132 J
Hence, the correct answer is 132 J.
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Answer:
a.) a = 0 ms⁻²
b.) a = 9.58 ms⁻²
c.) a = 7.67 ms⁻²
Explanation:
a.)
Acceleration (a) is defined as the time rate of change of velocity
Given data
Final velocity = v₂ = 0 m/s
Initial velocity = v ₁ = 0 m/s
As the space shuttle remain at rest for the first 2 minutes i.e there is no change in velocity so,
a = 0 ms⁻²
b.)
Given data
As the space shuttle start from rest, So initial velocity is zero
Initial velocity = v₁ = 0 ms⁻¹
Final velocity = v₂ = 4600 ms⁻¹
Time = t = 8 min = 480 s
By the definition of Acceleration (a)
a = 9.58 ms⁻²
c.)
Given data
As the space shuttle is at rest for first 2 min then start moving, So initial velocity is zero
Initial velocity = v₁ = 0 ms⁻¹
Final velocity = v₂ = 4600 ms⁻¹
Time = t = 10 min = 600 s
By the definition of Acceleration (a)
a = 7.67 ms⁻²
Complete Question:
Find the resistance of a wire of length 0.65 m, radius 0.25 mm and resistivity 3 * 10^{-6} ohm-metre.
Answer:
Resistance = 9.95 Ohms
Explanation:
<u>Given the following data;</u>
Length = 0.65 m
Radius = 0.25 mm to meters = 0.00025 m
Resistivity = 3 * 10^{-6} ohm-metre.
To find the resistance of the wire;
Mathematically, resistance is given by the formula;
Where;
- P is the resistivity of the material.
- L is the length of the material.
- A is the cross-sectional area of the material.
First of all, we would find the cross-sectional area of the wire.
Area of circle = πr²
Substituting into the equation, we have;
Area = 3.142 * (0.00025)²
Area = 3.142 * 6.25 * 10^{-8}
Area = 1.96 * 10^{-7} m²
Now, to find the resistance of the wire;
<em>Resistance = 9.95 Ohms </em>