Answer:
0.784 m
Explanation:
The motion of the ball is a projectile motion, which consists of two independent motions:
- a horizontal uniform motion, with constant speed of 
- a vertical accelerated motion, with constant acceleration 
towards the ground and initial position 
By looking at the vertical motion, we can find the time t at which the ball hits the ground, which is the time t at which the vertical position y becomes zero:
And now we can use the horizontal motion to find the total horizontal distance traveled during this time interval:
Answer:
Explanation:
Time taken to accelerate to 28 m /s
= 28 / 2 = 14 s
a ) Total length of time in motion
= 14 + 41 + 5
= 60 s .
b )
Distance covered while accelerating
s = ut + 1/2 at²
= 0 + .5 x 2 x 14²
= 196 m .
Distance covered while moving in uniform motion
= 28 x 41
= 1148 m
distance covered while decelerating
v = u - at
0 = 28 - a x 5
a = 5.6 m / s²
v² = u² - 2 a s
0 = 28² - 2 x 5.6 x s
s = 28² / 2 x 5.6
= 70 m .
Total distance covered
= 196 + 1148 + 70
= 1414 m
total time taken = 60 s
average velocity
= 1414 / 60
= 23.56 m /s .
Answer:
2*10^9electrons
Explanation:
Remember that the net force will be zero at terminal voltege so
Mg = 6πrng
At 35v
We have
qvr = 6πrng
q= 6 x 3.142* nx 2.6*10^-5/35
q,= 3.2x 10^ - 10C
So using n= q/e
= 3.2x 10^ - 10C/1.6*10-19
= 2*10^9electrons
Answer:
Explanation:
Let the bullets speed be V .
Kinetic energy = 1/2 mV² where m is mass of bullet
This energy is converted into heat Q which raises the temperature of target by Δ T .
Q = mc Δ T , m is mass , c is specific heat and Δ T is rise in temperature .
heat absobed by bullet
= .0075 x 130 x .040
= .039 J
heat absorbed by block of wood
= 17.5 x 1700 x .04
= 1190 J
Total heat absorbed
= 1190.039 J
So kinetic energy = heat absobed
= 1/2 x .0075 x V² = 1190.039
V² = 317343.73
V = 563.33 m /s
