Answer:
Explanation:
The ball was moving with velocity of 20 m /s earlier in horizontal direction . Due to kicking, additional V velocity was added to it at 40° because he kicked it at this angle but the ball travelled in the direction of resultant which was making an angle of 30° with the horizontal .
From the relation of inclination of resultant
Tan θ = V sinα / (u + V cosα) where α is angle between u and V , θ is inclination of resultant
Tan30 = 
20 + .766 V = 1.11 V
20 = .344 V
V = 58 m /s
To know the force , we shall apply concept of impulse
F x t = mv , F is force for time t creating a change of momentum mv
F x .1 = .4 x 58
F = 232 N
Short Answer
3: C
4: D
Problem Three
Remark
Somewhere we ought to be told that this is the Doppler Effect. I have never done a problem using this formula, so I think I'm doing it correctly, but no guarantees. My guess is that the frequency increases as it comes towards you and decreases as it moves away from you. I think that is correct.
Formula
<em><u>Givens</u></em>
- f' = observed frequency
- f = actual frequency
- v = velocity of sound or light waves.
- vo = velocity of observer (in both cases 0)
- vs = velocity of source.
f' = (v + vo) * f / (v - vs)
Solution
- v = 3*10^8 m/s
- f' = 1.1 f
- f = f
- vo = 0 We are standing still while all this is going on.
- vs = ???
f'/f = 1.1
1.1 = (3*10^8 + 0 ) / (3*10^8 - vs)
3.3*10^8 - 1.1*vs = 3*10^8
3.3*10^8 - 3*10^8= 1.1 vs
0.3 * 10^8 = 1.1 vs
2.73 * 10^7 = vs
The closest answer is 3.00 * 10^7 which is C
Problem Four
Here what is happening is that you are looking for the frequency resulting from a wave moving towards you at 1/2 the speed of sound. You are not moving.
<em><u>Givens</u></em>
- v = v
- vs = 1/2 v
- f ' = ?
- f = 1000 hz
- vo =0
f' = v/(v - 1/2v) * 1000
f' = v/ (1/2 v) * 1000
f' = 2 * 1000
f' = 2000 which is D
Answer:
Subducting convergent boundary
Explanation:
Generally, volcanoes occurs in both divergent and convergent boundaries. But the convergent boundary it occurs is usually associated with subduction.
Divergent boundary, plates move away from each other creating a new crust in the process. The diverging plates creates the space for magma to be squeezed through cracks and fissures. The magma's erupt to form volcanoes. In the Atlantic ocean the spreading of the plates causes an upwelling of magma through the crest of the Atlantic ridges. New oceanic crust are formed through this process. Sometimes the magma eruption forms volcanoes that are higher than the sea level.
Convergent boundary , plates collides with each other . But in the case of volcanoes existence , the collision should be between a denser plate(oceanic plates) and a less dense plates(continental plates) so that subduction can take place. The subducted plates (oceanic plates) creates trenches and get expose to high temperature and pressure as it sinks toward the mantle. The upper mantle rocks melts and migrate to the earth surface forming volcanoes . Over 75% of the volcanoes occur along the pacific basin where convergent boundary is dominant. Pacific ring of fire has one of the most number of volcanoes.
Answer:
velocity 1 second later = 59.8 m/s
Explanation:
Velocity final = Velocity initial + acceleration • time
Velocity final = 50m/s + 9.8m/s/s • 1s
Velocity final = 59.8 m/s
Answer:
The temperature is 90.4°C
Explanation:
See the attached for explanation
