KE = (1/2) (mass) (speed)²
KE = (1/2) (20 kg) (40 m/s)²
KE = (1/2) (20 kg) (1,600 m²/s²)
KE = (10 kg) (1,600 m²/s²)
KE = 16,000 Joules
ANSWER
T₂ = 10.19N
EXPLANATION
Given:
• The mass of the ball, m = 1.8kg
First, we draw the forces acting on the ball, adding the vertical and horizontal components of each one,
In this position, the ball is at rest, so, by Newton's second law of motion, for each direction we have,

The components of the tension of the first string can be found considering that they form a right triangle, where the vector of the tension is the hypotenuse,

We have to find the tension in the horizontal string, T₂, but first, we have to find the tension 1 using the first equation,

Solve for T₁,

Now, we use the second equation to find the tension in the horizontal string,

Solve for T₂,

Hence, the tension in the horizontal string is 10.19N, rounded to the nearest hundredth.
Answer:
V = 0.0806 m/s
Explanation:
given data
mass quarterback = 80 kg
mass football = 0.43 kg
velocity = 15 m/s
solution
we consider here momentum conservation is in horizontal direction.
so that here no initial momentum of the quarterback
so that final momentum of the system will be 0
so we can say
M(quarterback) × V = m(football) × v (football) ........................1
put here value we get
80 × V = 0.43 × 15
V = 0.0806 m/s
Answer:
Part a)

Part b)

Part c)

Explanation:
As we know that 5000 kg African elephant requires 70,000 Cal for basic needs per day
so we will have


so we have energy required per kg


Part a)
now we know that per kg the energy required will be same
so we have mass of the human is 68 kg
so energy required per day is given as


Part b)
Resting power is the rate of energy in Joule required per sec
so it is given as


Part c)
resting power given in the book is

so this is less than the power given

