Answer:
35.35 m
Explanation:
The following data were obtained from the question:
Initial velocity (u) = 20 m/s
Angle of projection (θ) = 30°
Acceleration due to gravity (g) = 9.8 m/s²
Range (R) =.?
The range (i.e how far away) of the ball can be obtained as follow:
R = u² Sine 2θ /g
R = 20² Sine (2×30) / 9.8
R = 400 Sine 60 / 9.8
R = (400 × 0866) / 9.8
R = 346.4 / 9.8
R = 35.35 m
Therefore, the range (i.e how far away) of the ball is 35.35 m
Assuming that the object starts at rest, we know the following values:
distance = 25m
acceleration = 9.81m/s^2 [down]
initial velocity = 0m/s
we want to find final velocity and we don't know the time it took, so we will use the kinematics equation without time in it:
Velocity final^2 = velocity initial^2 + 2 × acceleration × distance
Filling everythint in, we have:
Vf^2 = 0^2 + (2)(-9.81)(-25)
The reason why the values are negative is because they are going in the negative direction
Vf^2 = 490.5
Take the square root of that
Final velocity = 22.15m/s which is answer c
Answer:
Explanation:
heat lost by water will be used to increase the temperature of ice
heat gained by ice
= mass x specific heat x rise in temperature
1 x 2090 x t
heat lost by water in cooling to 0° C
= mcΔt where m is mass of water , s is specific heat of water and Δt is fall in temperature .
= 1 x 2 x 4186
8372
heat lost = heat gained
1 x 2090 x t = 8372
t = 4°C
There will be a rise of 4 degree in the temperature of ice.
If friction is acting along the plane upwards
then in this case we will have
For equilibrium of 100 kg box on inclined plane we have

also for other side of hanging mass we have

now we have




In other case we can assume that friction will act along the plane downwards
so now in that case we will have

also we have

now we have





<em>So the range of angle will be 23.45 degree to 37 degree</em>