Acceleration = (change in speed) / (time for the change)
change in speed = (ending speed) - (starting speed)
change in speed = (10 m/s) - (2 m/s) = 8 m/s
Acceleration = (8 m/s) / (4 sec)
Acceleration = (8/4) (m/s²)
<em>Acceleration = 2 m/s²</em>
Answer:
A. 4,9 m/s2
B. 2,0 m/s2
C. 120 N
Explanation:
In the image, 1 is going to represent the monkey and 2 is going to be the package. Let a_mín be the minimum acceleration that the monkey should have in the upward direction, so the package is barely lifted. Apply Newton’s second law of motion:

If the package is barely lifted, that means that T=m_2*g; then:

Solving the equation for a_mín, we have:

Once the monkey stops its climb and holds onto the rope, we set the equation of Newton’s second law as it follows:
For the monkey: 
For the package: 
The acceleration a is the same for both monkey and package, but have opposite directions, this means that when the monkey accelerates upwards, the package does it downwards and vice versa. Therefore, the acceleration a on the equation for the package is negative; however, if we invert the signs on the sum of forces, it has the same effect. To be clearer:
For the package: 
We have two unknowns and two equations, so we can proceed. We can match both tensions and have:

Solving a, we have

We can then replace this value of a in one for the sums of force and find the tension T:

Equation 1 :
m1 : m1a =T
Equation 2:m2 : m2a= F - T
Adding 1 and 2a=0.073
Placing in equation 1
we get T = 218.18N
Answer:
The sound intensity level in the car is 57.2 dB.
Explanation:
Sound intensity level in decibels, β = 10 log (I/I₀); where I = 0.525 × 10⁻⁶ W/m², I₀ = 1.0 × 10⁻¹² W/m²
β (dB) = 10 log ((0.525 × 10⁻⁶)/(1.0 × 10⁻¹²)) = 10 × 5.72 = 57.2 dB
Hope this Helps!!!