Answer:
In other words, Tension (Ft) = Force of gravity (Fg) = m × g. Assuming a 10 kg weight, then, the tension force is 10 kg × 9.8 m/s2 = 98 Newtons.
Explanation:
Answer:
2.62seconds
Explanation:
Echo occurs when sound reflects and causing a delay before getting to the listener.
Let x be the distance from between the source and the reflector
t be the time taken for the echo to occur
v be the velocity of sound in air.
Using the relationship 2x = vt
t = 2x/v
Given x = 450metres
v = 343m/s
t = 2(450)/343
t = 900/343
t = 2.62seconds
It will take 2.62 seconds for him to hear his own voice echo off of the wall.
Answer:
t = 5 10² s
Explanation:
Light is an electromagnetic wave that travels at a constant speed of 3 10⁸ m/s in vacuum.
The distance from the Sun to the Earth is 150 10⁶ km
Let's reduce the distance to the SI system
x = 150 10⁶ km (10³ m / 1 km) = 150 10⁹ m
Since the velocity is constant, we can use the uniform motion relations
v = x / t
t = x / v
let's calculate
t = 150 10⁹ / 3 10⁸
t = 5 10² s
Answer:
a) t =12[s]; b) x = 348[m]
Explanation:
We can solve this problem using the following kinematics equations:
a)
![v_{f}= v_{o}+a*t](https://tex.z-dn.net/?f=v_%7Bf%7D%3D%20v_%7Bo%7D%2Ba%2At)
where:
vf = final velocity = 12 [m/s]
vo= initial velocity = 6 [m/s]
a = acceleration = 0.5[m/s^2]
t = time [s]
Now clearing the time t, we have:
![t=\frac{v_{f} -v_{o} }{a} \\t = \frac{12-6}{0.5} \\t=12[s]](https://tex.z-dn.net/?f=t%3D%5Cfrac%7Bv_%7Bf%7D%20-v_%7Bo%7D%20%7D%7Ba%7D%20%5C%5Ct%20%3D%20%5Cfrac%7B12-6%7D%7B0.5%7D%20%5C%5Ct%3D12%5Bs%5D)
b)
We can calculate the displacement for the first 12 [s] then using the equation for the constant velocity we can calculate the other displacement for the 20[s].
![v_{f}^{2}= v_{o}^{2}+2*a*x_{1} \\therefore\\x_{1} =\frac{v_{f}^{2}-v_{o}^{2}}{2*a} \\x_{1} =\frac{12^{2}-6^{2}}{2*.5}\\x_{1} =108[m]](https://tex.z-dn.net/?f=v_%7Bf%7D%5E%7B2%7D%3D%20%20v_%7Bo%7D%5E%7B2%7D%2B2%2Aa%2Ax_%7B1%7D%20%5C%5Ctherefore%5C%5Cx_%7B1%7D%20%3D%5Cfrac%7Bv_%7Bf%7D%5E%7B2%7D-v_%7Bo%7D%5E%7B2%7D%7D%7B2%2Aa%7D%20%5C%5Cx_%7B1%7D%20%3D%5Cfrac%7B12%5E%7B2%7D-6%5E%7B2%7D%7D%7B2%2A.5%7D%5C%5Cx_%7B1%7D%20%3D108%5Bm%5D)
The we can calculate the second displacement for the constant velocity:
![x_{2} =x_{o}+v*t_{2} \\ x_{2} =0+12*(20)\\x_{2} =240[m]](https://tex.z-dn.net/?f=x_%7B2%7D%20%3Dx_%7Bo%7D%2Bv%2At_%7B2%7D%20%5C%5C%20x_%7B2%7D%20%20%3D0%2B12%2A%2820%29%5C%5Cx_%7B2%7D%20%3D240%5Bm%5D)
x = x1 + x2
x = 108 + 240
x = 348[m]
Momentum is Mass times Velocity