Answer:
Positive velocity and negative acceleration
Explanation:
An object moving in the positive direction has a positive velocity.
An object that's slowing down while moving in the positive direction has a negative acceleration.
Answer:
0.0018 W/m²
Explanation:
Power and intensity are related as:
P= 20.0 W (given)
r = 30.0 m (given)
Intensity in decibels:
Answer:
The velocity is 18.68m/s
Explanation:
Bernoulli's equation is applicable for stream line flow of a fluid. The flow must be steady and uniform flow. The Bernoulli's equation between inlet and outlet is written as:
P1/pg + V1/2g + Z1 = P2/pg + V2^2 + Z2
Where V1 and V2 are velocity of fluid at point 1 and 2b. The diameter of the tank too will be larger than that of the nozzle. Hence the velocity at point 1 will be 0.V1= 0
Substituting the values in to the equation
250 ×10^3/1000g + 0/g + 2.5 = 100×10^3/1000g + V2^2/2g + 0
250 + 2.5g = 100 + V2^2/2
250 + (2.5 × 9.8) = 100 V2^2/2
250 + 23.525- 100 = V2^2/2
174.525 = V2^2/2
Cross multiply
174.525 × 2 = V2^2
V2 = 349.05
V2 = Sqrt(349.05)
V2 = 18.68m/s
In order to understand the results of another scientist's work, any scientist
who reads the report MUST understand the measurement system in which
the result is described. Otherwise the result is meaningless to him.
Answer:
j
Explanation:
x = 4 t^2 - 2 t - 4.5
Position at t = 3 s
x = 4 (3)^2 - 2 (3) - 4.5 = 25.5 m
Velocity at t = 3 s
v = dx / dt = 8 t - 2
v ( t = 3 s) = 8 x 3 - 2 = 22 m/s
Acceleration at t = 3 s
a = dv / dt = 8
a ( t = 3 s ) = 8 m/s^2
When is the velocity = 0
v = 0
8 t - 2 = 0
t = 0.25 second
When is the position = 0
x = 0
4 t^2 - 2 t - 4.5 = 0
t = 1.4 second