Answer:
6.93 km/h
Explanation:
To calculate her average speed, we need the "speed" formula, which is:
average speed = distance / time
You plug in your numbers and it will give you the answer.
Speed = 4.5km/0.65hr
= 6.923 km/h
There isnt enough information to answer the question, the missing variable is "distance from said falling spot and ground"
The total momentum of the system has to be conserved to satisfy the principle of conservation of momentum. Before the ball hits the bottle, the momentum of the system is 0.4 x 18 = 7.2 kg m/s
The momentum of the bottle after being hit is 0.2 x 25 = 5 kg m/s
So the momentum of the ball now is 7.2 - 5 = 2.2 kg m/s
Hence its velocity is 2.2/0.4 = 5.5 m/s
Answer:
A stone that is dropped down into an empty well
Answer:
17.565 kgm/s
Explanation:
Momentum = mass × velocity
I = mv..................... Equation 1
But we can calculate the value of v using the equation of motion under gravity.
v² = u²+2gs............. Equation 2
Where u = initial velocity, s = maximum heigth, g = acceleration due to gravity.
Given: u = 0 m/s (at the maximum heigth), s = 7.0 m.
Constant: g = 9.8 m/s²
Substitute these values into equation 2
v² = 0²+ 2×7×9.8
v² = 137.2
v = √137.2
v = 11.71 m/s.
Also given: m = 1.50 kg
substitute these values into equation 1
Therefore,
I = 1.5×11.71
I = 17.565 kgm/s
