The position of an oscillating mass is given by:
where A is the amplitude of the oscillation, the angular frequency and t the time.
The velocity of the oscillating mass can be found by calculating the derivative of the position:
In this problem, A=2.0 cm and , so if we substitute these data and t=0.4 s we can find the velocity at t=0.4 s:
Answer:
Average speed: 0.5 m/s. Average velocity: 0
Explanation:
Average speed is given by:
where
d is the total distance covered (the length, of one lap of the track, so d = 400 m)
t is the time taken to cover that distance (so, t = 800 s)
Substituting,
Instead, average velocity is defined as
where this time,
d is the displacement, which is the vector connecting the starting point to the final point of the motion
t is still the time taken (800 s)
However, in this case the walker starts and finishes his trip at the same point: therefore, the displacement is zero (d=0), and this means that the average velocity is zero as well.
10% is about how much travels down from level to level
Answer:
Heat energy required = 687.96 kJ
Explanation:
Heat energy required, H = mCΔT.
Mass of cooking oil, m = 2.34 kg = 2340 g
Specific heat of cooking oil, C = 1.75 J/(g⋅°C)
Initial temperature = 23 °C
Final temperature = 191 °C
Change in temperature, ΔT = 191 - 23 = 168 °C
Substituting values
H = mCΔT
H = 2340 x 1.75 x 168 = 687960 J = 687.96 kJ
Heat energy required = 687.96 kJ