Answer:
e = 0.0898m
v = 2.07m/s
Explanation:
a) According to Hooke's law
F = ke
e is the extension
k is the spring constant
Since F = mg
mg = ke
e = mg/k
Substitute the given value
e = 1.1(9.8)/120
e = 10.78/120
e = 0.0898m
Hence it is stretched by 0.0898m from its unstrained length
2) Total Energy = PE+KE+Elastic potential
Total Energy = mgh +1/2mv²+1/2ke²
Substitute the given value
5.0= 1.1(9.8)(0.2)+1/2(1.1)v²+1/2(120)(0.0898)²
Solve for v
5.0 = 2.156+0.55v²+0.48338
5.0-2.156-0.48338= 0.55v²
2.36 =0.55v²
v² = 2.36/0.55
v² = 4.29
v ,= √4.29
v = 2.07m/s
Hence the required velocity is 9.28m/s
Answer:
Explanation:
The energy difference between the energy levels involved in the transition of the electron is directly proportional to the frequency of the emitted photon:
Where h is the Planck constant. The photon's frequency is inversely proportional to its wavelegth:
Here c is the speed of light. Replacing (2) in (1):
Answer:
750 people
Explanation:
From the question,
Number of people in the city = population density×Area of the city
N = D×A.......................... Equagtion 1
Where N = Number of people in the city, D = population density, A = Area of the city.
Given: D = 50 people per square kilometer, A = 1.5×10 square kilometer.
Substitute into equation 1
N = 50(1.5×10)
N = 750 people.
Hence the total number of people in the city is 750 people.
Underhand serve is a type of volleyball serve in which a player holds the ball with one hand and swings the other hand in an arc motion, striking under the ball with a fist to put it into play. An underhand serve is the most common serve for beginners.
The air movements toward the equator are called trade winds, which are warm, steady breezes that blowalmost continuously. The Coriolis Effect makes the trade winds appear to be curving to the west, whether they are traveling to the equator from the south or north. Answer trade wind
