Answer:
a) F = 527.65 N, Force applied is upwards.
b)F = - 527.65 N, where, negative sign depicts Force is applied downwards.
Explanation:
Data provided:
Weight of the firefighter = 756 N
Mass of the firefighter = 756/9.8 = 77.14 Kg
Acceleration, a = 2.96 m/s²
a) In the absence of the pole the firefighter would have been moving down with an acceleration of 9.8 m/s (i.e the acceleration due to the gravity), but due to the presence of the pole the acceleration of the firefighter has been reduced. thus, a force is applied by the pole on the firefighter to reduce the acceleration.
therefore, we have
F = ma(net) = 77.14 × (9.8-2.96) = 527.65 N, Force applied is upwards.
B) According to the Newton's third law, the force will be equal and opposite to the force in the part a)
thus, we have
F = - 527.65 N
Answer:
3.7 km/h
Explanation:
Let's call v the proper speed of the boat and v' the speed of the water in the river.
When the boat travels in the direction of the current, the speed of the boat is:
v + v'
And it covers 50 km in 3 h, so we can write
(1)
When the boat travels in the opposite direction, the speed of the boat is
v - v'
And it covers 50 km in 5.4 h, so
(2)
So we have a system of two equations: by solving them simultaneously, we find the value of v and v':
Subtracting the second equation from the first one we get:
So, the speed of the water is 3.7 km/h.
Answer:
true a good refrigiant needs a high boiling point
Answer:
The car that is accelerating is B a car that rounds a curve at a constant speed
Explanation:
Although all of the cars are at a constant speed or not moving acceleration is the change in speed or the change of directions therefore making the only car changing directions your answer.
Electricity is always going to take the path of least resistance to ground. The rubber in your shoes is not a conductor of electricity, therefore you are not completing the circuit and you don't get shocked. Your bare feet, on the other hand ARE conductors of electricity, so when you hold the wire, you complete the circuit and become the path of least resistance to ground... ZAP!
