Answer:
The rock's final speed at the required altitude will be 42.24 m/s.
Explanation:
Let's start by finding the initial vertical speed.
Vertical Speed = 1.61 * Sin (53.2°)
Vertical Speed = 0.8 m/s
We want to know the speed of the rock when it is at an altitude of 91 km.
The total displacement of the rock from its starting position will thus be equal to -91 km
We can use this in the following equation:


t = 4.3918 seconds
Thus it takes 4.3918 seconds to reach the required altitude. We can now find the speed as follows:



Thus the rock's final speed at the required altitude will be 42.24 m/s.
Answer:
distance = 33.124 meters
Explanation:
To solve this question, we will use one of the equations of motion which is:
s = ut + 0.5a * t^2
where:
s is the distance that we want to get
u is the initial velocity = 0
a is the acceleration due to gravity = 9.8 m/sec^2
t is the time = 2.6 sec
Substitute with the givens in the equation to get the distance as follows:
s = ut + 0.5a * t^2
s = (0)(2.6) + 0.5(9.8)(2.6)^2
s = 33.124 meters
Hope this helps :)
Answer:

Explanation:
Given that
Mass of rifle = M
Initial velocity ,u= 0
Mass of bullet = m
velocity of bullet = v
Lets take final speed of the rifle is V
There is no any external force ,that is why linear momentum of the system will be conserve.
Initial linear momentum = Final linear momentum
M x 0 + m x 0 = M x V + m v
0 = M x V + m v

Negative sign indicates that ,the recoil velocity will be opposite to the direction of bullet velocity.
Answer : The power absorbed by the bulb is, 0.600 W
Explanation :
As we know that,
Power = Voltage × Current
Given:
Voltage = 3 V
Current = 200 mA = 0.200 A
Conversion used : (1 mA = 0.001 A)
Now put all the given values in the above formula, we get:
Power = Voltage × Current
Power = 3V × 0.200 A
Power = 0.600 W
Thus, the power absorbed by the bulb is, 0.600 W