Answer:
35.6 s
Explanation:
The power through the resistor is given by:
where V=9.0 V is the voltage and I=0.50 A is the current. Substituting into the formula, we find
The power is also equal to:
where W is the work done while t is the time taken. Since we know the work done, W=160 J, we can re-arrange the equation to find the time taken:
Answer:
The percentage change in frequency is 10%.
Explanation:
Given that,
Amplitude decreases by 1/10 per second.
Resonance = 10 Hz
We need to calculate the change in frequency
Using formula of change in frequency
Put the value into the formula
We need to calculate the resonant frequency
Using formula of resonant frequency
Put the value into the formula
We need to calculate the percentage change in frequency
Using formula of percentage change in frequency
Hence, The percentage change in frequency is 10%.
Answer: after 1.75 seconds
Explanation:
The only force acting on the ball is the gravitational force, so the acceleration will be:
a = -9.8 m/s^2
the velocity can be obtained by integrating over time:
v = -9.8m/s^2*t + v0
where v0 is the initial velocity; v0 = -7.95 m/s.
v = -9.8m/s^2*t - 7.95 m/s.
For the position we integrate again:
p = -4.9m/s^2*t^2 - 7.95 m/s*t + p0
where p0 is the initial position: p0 = 29m
p = -4.9m/s^2*t^2 - 7.95 m/s*t + 29m
Now we want to find the time such that the position is equal to zero:
0 = -4.9m/s^2*t^2 - 7.95 m/s*t + 29m
Then we solve the Bhaskara's equation:
Then the solutions are:
t = (7.95 + 25.1)/(-9.8) = -3.37s
t = (7.95 - 25.1)/(-9.8) = 1.75s
We need the positive time, then the correct answer is 1.75s