Answer:
Explanation:
horizontal component of velocity of throw = 20 cos20 = 18.8 m /s
vertical downwards component = 20 sin20 = 6.84 m /s
time to displace by height 30 m = t , initial velocity u = 6.84 m /s
h = ut + 1/2 gt²
30 = 6.84 t + .5 x 9.8 t²
4.9 t² + 6.84 t - 30 = 0
t = - 6.84 ±√( 6.84² + 4 x 4.9 x 30 ) / 2x 4.9
= - 6.84 ±√( 46.78 + 588 ) / 9.8
= - 6.84 ±√(634.78 ) / 9.8
= - 6.84 ±25.2 / 9.8
= 1.87 s
horizontal displacement in 1.87 s
= 18.8 x 1.87
= 35.15 m .
Answer:
3.50 m/s^2
Explanation:
the race is of 100 m.
time after which Marge crosses the finish line after t= 10.8 sec
time take by her to attain maximum speed t_o= 2.20 sec
a= ![\frac{v}{t_0}](https://tex.z-dn.net/?f=%5Cfrac%7Bv%7D%7Bt_0%7D)
we know that
s= ut +1/2at^2
100= v![100= v\times10.8+ 0.5a10.8^2](https://tex.z-dn.net/?f=100%3D%20v%5Ctimes10.8%2B%200.5a10.8%5E2)
put a=
here t_o= 2.20 sec
![100=v\times10.8+ 0.5 \frac{v}{2.20} 10.8^2](https://tex.z-dn.net/?f=100%3Dv%5Ctimes10.8%2B%200.5%20%5Cfrac%7Bv%7D%7B2.20%7D%2010.8%5E2)
v= 7.72 m/s
now Marge acceleration a=
= 3.50 m/s^2
Answer:
If you know the total current and the voltage across the whole circuit, you can find the total resistance using Ohm's Law: R = V / I. For example, a parallel circuit has a voltage of 9 volts and total current of 3 amps. The total resistance RT = 9 volts / 3 amps = 3 Ω.
Explanation:
We will measure all angles from West, the negative x-axis and divide the journey into 3 parts:
P1 = 370y
P2 = 410cos(45)x + 410sin(45)y = 290x + 290y
P3 = 370cos(270 - 28)x + 370sin(270 - 28) = -174x - 327y
Overall displacement:
x = 290 - 174 = 116 m
y = 370 + 290 - 327 = 333 m
displacement = √(116² + 333²)
= 353 m
Direction:
tan(∅) = y/x
∅ = tan⁻¹ (333 / 116)
∅ = 70.8° from West.
The work done by the child while pulling the wagon is given by:
![W=Fd](https://tex.z-dn.net/?f=%20W%3DFd%20)
where F is the force applied and d is the distance through which the wagon has been moved.
In this problem, F=22 N and d=4.3 m, therefore the work done by the child is
![W=Fd=(22 N)(4.3 m)=94.6 J](https://tex.z-dn.net/?f=%20W%3DFd%3D%2822%20N%29%284.3%20m%29%3D94.6%20J%20)