Answer:
The resultant velocity = 3.16 m/s
Explanation:
Since the boat is moving North of the direction of the riverflow, the river would either be flowing westward or Eastward. The two motions form a right angle triangle with the resultant velocity being the hypotenuse of the traingle.
The resultant velocity will be given as ;
R² = B² + r²
Where B is the velocity of the boat and r is the velocity of the river
R² = 3² + 1²
R² = 10
R = √10 = 3.16 m/s
Therefore, the resultant velocity = 3.16 m/s
1. sliding 2. static 4. rolling
Complete question:
A pendulum of length L = 48.5 cm and mass m = 169 g is released from rest when the cord makes an angle of 65.4° with the vertical. What is the speed of the mass (m/s) upon reaching its lowest point?
Answer:
The speed of the mass upon reaching its lowest point is 2.36m/s
Explanation:
To obtain the speed of the mass upon reaching its lowest point, we apply the principle of conservation of mechanical energy. At the lowest point, the kinetic energy of the pendulum is maximum and at the highest point, the vertical displacement is maximum, thus potential energy is maximum.
Kinetic energy at the lowest point = Potential energy at the highest point
From my explanation above, h is the vertical displacement, when potential energy of the pendulum is maximum. Considering a right angled triangle, this vertical displacement, h is the adjacent of the triangle, and it is equal to
L - Lcosθ.
h = 48.5 - 48.5cos(65.4) = 28.31 cm = 0.2831 m
Therefore, the speed of the mass upon reaching its lowest point is 2.36m/s
The two possible distances that you might infer your friends swam while the lights were out are 25 m and 75 m.
Answer:
Explanation:
So you have to measure the distance covered by your friend in a time gap of 86 s. And the average velocity is given as 0.29 m/s.
Then as per the mathematical calculation of velocity, distance can be measured as the product of velocity with time interval.
Distance = Velocity × Time Interval
Distance = 0.29 m/s×86 s = 24.94 m.
So based on this calculation, one of the possible distance inferred by you will be 24.94 m.
Another possible distance can be guessed from the statements provided. So if the length of pool is 50 m, then covering halfway in opposite direction to his starting direction means completion of one full length i.e., 50 m and then halfway of that 50 m which is 25m, so totally 50 +25 = 75 m.
So in other way, we can assume that your friend has covered 75 m distance during the light out.
Thus, the two possible distances that you might infer your friends swam while the lights were out are 25 m and 75 m.
