Answer:Take into account the the Earths gravity is 9.8 meters a second
Explanation:
Gravity pulls down on the ball at g=-9.81 m/s^2. Up is positive, down is negative.The ball started at a certain initial velocity of Vi m/s. Time it took is t=4s. Final velocity is Vf=0 m/s, because at the highest point the ball stops moving.
Vf=(g*t)+Vi
Rearrange for Vi.
Vi=Vf-(g*t)
Vi=0-(-9.81*4)=39.24 m/s (upward)
Think about it this way for the non-mathematical approach. The ball stops at the top. The initial velocity gets reduced by 9.81 m/s every second, and reaches 0 m/s at the top. It took 4 seconds, so 9.81*4 is equal to the initial upward velocity.
Answer:
Explanation:
Given the mass of the crate = 10kg
initial speed of the crate = 1.50m/s
pulling force F = 100N
angle of inclination = 20°
Coefficient of kinetic friction = 0.400
Distance traveled by the crate d = 5.00m
Application of newton's second law perpendicular to the inclined plane is used and the detailed calculation is as shown in the attached file.
Answer:
10.93m/s with the assumption that the water in the lake is still (the water has a speed of zero)
Explanation:
The velocity of the fish relative to the water when it hits the water surface is equal to the resultant velocity between the fish and the water when it hits it.
The fish drops on the water surface vertically with a vertical velocity v. Nothing was said about the velocity of the water, hence we can safely assume that the velocity if the water in the lake is zero, meaning that it is still. Therefore the relative velocity becomes equal to the velocity v with which the fish strikes the water surface.
We use the first equation of motion for a free-falling body to obtain v as follows;
v = u + gt....................(1)
where g is acceleration due to gravity taken as 9.8m/s/s
It should also be noted that the horizontal and vertical components of the motion are independent of each other, hence we take u = 0 as the fish falls vertically.
To obtain t, we use the second equation of motion as stated;
Given; h = 6.10m.
since u = 0 for the vertical motion; equation (2) can be written as follows;
substituting;
Putting this value of t in equation (1) we obtain the following;
v = 0 + 9.8*1.12
v = 10.93m/s
Answer:
44 Ohms
Explanation:
Use Ohm's law:
(Resistance) = (Voltage) / (Current)
(Resistance) = 88V / 2 A = 44 Ohms
Answer:
Explanation:
Given that
Force constant k=8.6N/m
Weight =64g=64/1000=0.064kg
Extension is 45mm=45/1000= 0.045m
It will have it highest spend when the Potential energy is zero
Therefore energy in spring =change in kinetic energy
Ux=∆K.e
½ke² = ½mVf² — ½mVi²
Initial velocity is 0, Vi=0m/s
½ke² = ½mVf²
½ ×8.6 × 0.045² = ½ ×0.064 ×Vf²
0.0087075 = 0.032 Vf²
Then, Vf² = 0.0087075/0.032
Vf² = 0.2721
Vf=√0.2721
Vf= 0.522m/s
The time it will have this maximum velocity?
Using equation of motion
Vf= Vi + gr
0.522= 0+9.81t
t=0.522/9.81
t= 0.0532sec
t= 53.2 milliseconds