Answer:
<h3><em>
28.01m/s.</em></h3>
Explanation:
Given maximum height reached by the ball as H = 40 metres
Since the ball rises straight up when hit by a ball, then the angle of launch will be perpendicular to the ground and that is 90°.
To determine the upward speed of the ball in meters per second after it got struck by the bat, we will use the formula for calculating the maximum height according to projectile motion;
Maximum Height H =
where;
u is the speed of the ball
is the angle of launch
g is the acceleration due to gravity = 9.81m/s²
Substituting the given parameters into the formula;

<em>Hence the upward speed of the ball in meters per second after it got struck by the bat is 28.01m/s.</em>
Answer:
To unlock a door and indicate to the person that the door is now unlocked
Explanation:
Schools all have doors locked. Visitors/parents need to press a button. That creates a buzz sound in the office, secretary presses a button to unlock the door. The person trying to enter the school hears a buzz and the secretary telling them to enter the building.
Answer:
0.4113772 s
Explanation:
Given the following :
Mass of bullet (m1) = 8g = 0.008kg
Initial horizontal Velocity (u1) = 280m/s
Mass of block (m2) = 0.992kg
Maxumum distance (x) = 15cm = 0.15m
Recall;
Period (T) = 2π√(m/k)
According to the law of conservation of momentum : (inelastic Collison)
m1 * u1 = (m1 + m2) * v
Where v is the final Velocity of the colliding bodies
0.008 * 280 = (0.008 + 0.992) * v
2.24 = 1 * v
v = 2.24m/s
K. E = P. E
K. E = 0.5mv^2
P.E = 0.5kx^2
0.5(0.992 + 0.008)*2.24^2 = 0.5*k*(0.15)^2
0.5*1*5.0176 = 0.5*k*0.0225
2.5088 = 0.01125k
k = 2.5088 / 0.01125
k = 223.00444 N/m
Therefore,
Period (T) = 2π√(m/k)
T = 2π√(0.992+0.008) / 233.0444
T = 2π√0.0042910
T = 2π * 0.0655059
T = 0.4113772 s
2,062,305 2,062,305 <span>2,062,305</span>
Answer:
2.2nC
Explanation:
Call the amount by which the spring’s unstretched length L,
the amount it stretches while hanging x1
and the amount it stretches while on the table x2.
Combining Hooke’s law with Newton’s second law, given that the stretched spring is not accelerating,
we have mg−kx1 =0, or k = mg /x1 , where k is the spring constant. On the other hand,
applying Coulomb’s law to the second part tells us ke q2/ (L+x2)2 − kx2 = 0 or q2 = kx2(L+x2)2/ke,
where ke is the Coulomb constant. Combining these,
we get q = √(mgx2(L+x2)²/x1ke =2.2nC