Answer:
33.6 Ns backward.
Explanation:
Impulse: This can be defined as the product of force and time. The S.I unit of impulse is Ns.
From Newton's second law of motion,
Impulse = change in momentum
I = mΔv................................. Equation 1
Where I = impulse, m = mass of the skater, Δv = change in velocity = final velocity - initial velocity.
Given: m = 28 kg, t = 0.8 s, Δv = -1.2-0 = -1.2 m/s (Note: the initial velocity of the skater = 0 m/s)
Substituting into equation 1
I = 28(-1.2)
I = -33.6 Ns
Thus the impulse = 33.6 Ns backward.
The Avogadro’s number is used to represent the number of elementary entities that exist in one mole of a compound.
<h3>What is the Avogadro’s number?</h3>
The Avogadro’s number is used to represent the number of elementary entities that exist in one mole of a compound. The numerical value of the Avogadro’s number is obtained as 6.02 x 10^23 and consists of the atoms, molecules and ions in the compound.
The scientist Josef Loschmidt strengthened the Avogadro’s number by obtaining the number of particles in one cubic centimeter of gas under standard conditions.
Learn more about Avogadro's number:brainly.com/question/11907018
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Answer:
The man's total displacement is equal to 0.
Explanation:
Given that,
A man ran a 5 mile race. The race looped around a city park and back to the starting line.
We need to find the total displacement of the man.
We know that,
Displacement = shortest path covered
Also,
Displacement = final position - initial position
As it reaches back to its starting line, it means, the displacement is equal to 0.
Hence, the man's total displacement is equal to 0.
Answer:
21.85 C
Explanation:
mass of iron = 1.5 kg, initial temperature of iron, T1 = 500 C
mass of water = 20 kg, initial temperature of water, T2 = 18 C
let T be the equilibrium temperature.
Specific heat of iron = 449 J/kg C
specific heat of water = 4186 J/kg C
Use the principle of caloriemetry
heat lost by the hot body = heat gained by the cold body
mass of iron x specific heat of iron x decrease in temperature = mass of water x specific heat of water x increase in temperature
1.5 x 449 x (500 - T) = 20 x 4186 x (T - 18)
336750 - 673.5 T = 83720 T - 1506960
1843710 = 84393.5 T
T = 21.85 C
Answer:
The boat will move in the direction of the force exerted.
Explanation:
To describe the motion of the boat, we shall first obtain the net force acting on the boat. This can be obtained as illustrated below:
From the question given above, the following data were obtained:
Force exerted (Fₑ) = 300 N
Resistive force (Fᵣ) = 250 N
Net force (Fₙ) =?
Fₙ = Fₑ – Fᵣ
Fₙ = 300 – 250
Fₙ = 50 N
Thus, the net force acting on the boat is 50 N in the direction of the force exerted.
Since the net force is in the direction of the force exerted, the boat will move in the direction of the force exerted..!
