Answer: 900
Explanation: Force equals mass x acceleration F=M×A
For vertical motion, use the following kinematics equation:
H(t) = X + Vt + 0.5At²
H(t) is the height of the ball at any point in time t for t ≥ 0s
X is the initial height
V is the initial vertical velocity
A is the constant vertical acceleration
Given values:
X = 1.4m
V = 0m/s (starting from free fall)
A = -9.81m/s² (downward acceleration due to gravity near the earth's surface)
Plug in these values to get H(t):
H(t) = 1.4 + 0t - 4.905t²
H(t) = 1.4 - 4.905t²
We want to calculate when the ball hits the ground, i.e. find a time t when H(t) = 0m, so let us substitute H(t) = 0 into the equation and solve for t:
1.4 - 4.905t² = 0
4.905t² = 1.4
t² = 0.2854
t = ±0.5342s
Reject t = -0.5342s because this doesn't make sense within the context of the problem (we only let t ≥ 0s for the ball's motion H(t))
t = 0.53s
Answer:
<h2>
128.61 Watts</h2>
Explanation:
Average power done by the torque is expressed as the ratio of the workdone by the toque to time.
Power = Workdone by torque/time
Workdone by the torque = 
= 
I is the rotational inertia = 16kgm²
To get the angular acceleration, we will use the formula;
Workdone by the torque = 16 * 1.28 * 12.56
Workdone by the torque = 257.23 Joules
Average power done by the torque = Workdone by torque/time
= 257.23/2.0
= 128.61 Watts
The Two examples of contact forces are:
- frictional force
- Contact force.
The two examples of non contact forces are:
- Gravitational force
- magnetic force.
Contact forces happens due to the contact between two objects
Non Contact forces happens because there is no contact between two objects. There is no attraction.
A = delta v over delta t delta v is calculated with final velocity less initial velocity then delta v is equals to 20 - 0 that is 20m/s and to calculate delta t is like delta v is final time less initial time as initial time always is 0 the delta t is equals to 10s then a = 20/10 then acceleration is 10m/s^2 (remember that is squared)
