Answer:
v = 42.92 m/s
Explanation:
Given,
initial speed of the ball, v = 11 m/s
time taken to hit the ground = 5.5 m/s
velocity of the ball just before it hit the ground, v = ?
time taken by the ball to reach the maximum height
using equation of motion
v = u + at
final velocity = 0 m/s
0 = 11 - 9.8 t
t = 1.12 s.
time taken by the ball to reach the water from the maximum height
t' - 5.5 -1.12 = 4.38 s
using equation of motion for the calculation of speed just before it hit the water.
v = u + a t
v = 0 + 9.8 x 4.38
v = 42.92 m/s
Velocity of the ball just before it reaches the water is equal to v = 42.92 m/s
Answer:
4miles/hour
Explanation:
the solution for this question requires that the quantities are converted to the appropriate units as required by the question.
Rate in miles per hour = distance in miles / time in hour
to convert 12 minutes to hours; recall that 60 minutes make 1 hour
12 minutes to hour = 12/60 = 0.2hr
to convert 4224 feet to miles; recall 5280 feet is equivalent to 1 mile
4224 feet to miles = 4224/5280 = 0.8 miles
∴ rate = 0.8 / 0.2
rate = 4 miles per hour
the constant rate in miles per hour = 4 miles/hour
Answer:
6400 W (or) 6.4 KW
Explanation:
Formula we use,
→ P = I²R
Let's solve for the power of device,
→ P = I²R
→ P = (8)² × 100
→ P = 64 × 100
→ [ P = 6400 W ]
Hence, the power is 6400 W.
Answer:
<em>A = 6.9 cm</em>
Explanation:
<u>Simple Harmonic Motion</u>
A mass-spring system is a common example of a simple harmonic motion device since it keeps oscillating when the spring is stretched back and forth.
If a mass m is attached to a spring of constant k and they are set to oscillate, the angular frequency of the motion is

The equation for the motion of the object is written as a sinusoid:

Where A is the amplitude.
The instantaneous speed is computed as the derivative of the distance

And the maximum speed is

Solving for the amplitude

Computing w

Calculating A


A heat pump has a coefficient of performance of 7.05. If the heat pump absorbs 20 cal of heat from the cold outdoors in each cycle, find the heat expelled to the warm indoors. Answer in units of cal. I believe COP (heating mode) : 7.05 and COP = Qh/W Qc = 20 cal so I have to find Qh= ? cal I dont know an equation to put all this together? Please help, thank you.