Answer:
a. Acceleration, a = 1.88 m/s²
b. Time, t = 7.87 seconds.
Explanation:
Given the following data;
Initial velocity, U = 14.5m/s
Final velocity, V = 29.3m/s
Distance, S = 172m
a. To find the acceleration of the speedboat;
We would use the third equation of motion;
V² = U² + 2aS
Substituting into the formula
29.3² = 14.5² + 2a*172
858.49 = 210.25 + 344a
344a = 858.49 - 210.25
344a = 648.24
a = 648.24/344
Acceleration, a = 1.88 m/s²
b. To find the time;
We would use the first equation of motion;
V = U + at
29.3 = 14.5 + 1.88t
1.88t = 29.3 - 14.5
1.88t = 14.8
Time, t = 14.8/1.88
Time, t = 7.87 seconds.
Answer:
Average speed is total distance divided by total time.
v = d / t
Pathogens are microorganisms that cause infectious diseases. Bacteria and viruses are the main pathogens in the world today.
The major problem that pathogen cause in society is that they are the agents of infection and disease.
An infection results when a pathogen invades the body and begins growing within a host. A disease results when tissue function is impaired due to an infection.
Due to diseases, affected people can not work which negatively affects the economy, and the sick may end up dying causing a lot of grief, and robbing society of a father, a mother or child.
The government has to put money aside for health care which would otherwise have been used for other things to help the society.
Answer:
Explanation:
fundamental frequency, f = 250 Hz
Let T be the tension in the string and length of the string is l ans m be the mass of the string initially.
the formula for the frequency is given by
.... (1)
Now the length is doubled ans the tension is four times but the mass remains same.
let the frequency is f'
.... (2)
Divide equation (2) by equation (1)
f' = √2 x f
f' = 1.414 x 250
f' = 353.5 Hz
Explanation:
For each object, the initial potential energy is converted to rotational energy and translational energy:
PE = RE + KE
mgh = ½ Iω² + ½ mv²
For the marble (a solid sphere), I = ⅖ mr².
For the basketball (a hollow sphere), I = ⅔ mr².
For the manhole cover (a solid cylinder), I = ½ mr².
For the wedding ring (a hollow cylinder), I = mr².
If we say k is the coefficient in each case:
mgh = ½ (kmr²) ω² + ½ mv²
For rolling without slipping, ωr = v:
mgh = ½ kmv² + ½ mv²
gh = ½ kv² + ½ v²
2gh = (k + 1) v²
v² = 2gh / (k + 1)
The smaller the value of k, the higher the velocity. Therefore:
marble > manhole cover > basketball > wedding ring
