Answer:
Explanation:
Assume that a single baby cries at X db
4 babies crying would be X + 10log₁₀(4) = X + 6 db
Answer:
1.2 A
Explanation:
From the diagram attached, The three resistors are parallel because the each ends of the resistors are connected together. Since they are in parallel, the voltage across each resistor is the same. The voltage source connected in parallel to the resistors is 60 V. Therefore the voltage across the 50 Ω resistor is 60 V. Using ohm law:
Voltage (V) = Current (I) × Resistance (R)
V = IR
I = V/R
I = 60 V/ 50 Ω
I = 1.2 A
The current in the 50 Ω resistor is 1.2 A
Answer:
Coefficient of static friction will be equal to 0.642
Explanation:
We have given acceleration 
Acceleration due to gravity 
We have to find the coefficient of static friction between truck and a cabinet will
We know that acceleration is equal to
, here
is coefficient of static friction and g is acceleration due to gravity
So 
So coefficient of static friction will be equal to 0.642
Answer:
a) 17.49 seconds
b) 13.12 seconds
c) 2.99 m/s²
Explanation:
a) Acceleration = a = 1.35 m/s²
Final velocity = v = 85 km/h = 
Initial velocity = u = 0
Equation of motion

Time taken to accelerate to top speed is 17.49 seconds.
b) Acceleration = a = -1.8 m/s²
Initial velocity = u = 23.61\ m/s
Final velocity = v = 0

Time taken to stop the train from top speed is 13.12 seconds
c) Initial velocity = u = 23.61 m/s
Time taken = t = 7.9 s
Final velocity = v = 0

Emergency acceleration is 2.99 m/s² (magnitude)
1) B. Energy is the ability to do work
2) C. Energy is conserved, it just goes from one form to another.
3) Work = Force x displacement
= 300 x 100 = 30,000 Joules
4) leaning a brick because no displacement is taking place.
5) They change the amount/strength or direction of the force needed.
6) Less force is needed and applied over a longer distance.
7) Heat is the flow of thermal energy from one object to another.