Let us assume the upstream rowing rate of Alicia = x
Let us assume the downstream rowing rate of Alicia = y
We already know that
Travelling time = Distance traveled/rowing rate
Then
6/(x + 3) = 4/x
6x = 4x + 12
6x - 4x = 12
2x = 12
x = 6
Then
Rowing rate of Alicia going upstream = 6 miles per hour
Rowing rate of Alicia going downstream = 9 miles per hour.
Answer:
(a) 1.414 km
(b) 1.06 m/s
Explanation:
(a) For John:
Distance = 1 km north and then 1 km east
Speed = 1.5 m/s
total distance traveled = 1 + 1 = 2 km = 2000 m
Time taken to travel = Distance / speed
t = 2000 / 1.5 = 1333.3 seconds
Displacement = 
(b) For jane :
Time is same as john = 1333.33 second
Distance = 1.414 km = 1414 m
Speed = distance / time = 1414 / 1333.33 = 1.06 m/s
Answer:
Sam will do 1152 J of work to stop the boat
Explanation:
Work: This is defined as the product of force and distance, the S.I unit of work is Joules. At any point in science, during calculation Energy and worked can be interchange because they have the same unit.
E = W = 1/2mv²................ Equation 1
Where E = energy, W = work, m = mass, v = velocity.
Given: m = 900 kg, v = 1.6 m/s
Substituting these values into equation 1
W = 1/2(900)(1.6)²
W = 450×2.56
W = 1152 J.
Therefore Sam will do 1152 J of work to stop the boat
I see a pillow
But you see...this bobcat
Cute ain’t it?
Answer:
It's energy will double.
Explanation:
This is because energy, E, is related to frequency, f, by:
E = hf
Where h = Planck's constant
So, double frequency will be 2f
=> E(2f) = 2hf = 2E.
Hence, energy is doubled.
