consider the motion of con from top to bottom
Y = vertical displacement = 1000 m
a = acceleration due to gravity = 9.8 m/s²
v₀ = initial velocity at the top = 0 m/s
v = final velocity at the bottom = ?
using the kinematics equation
v² = v²₀ + 2 aY
v² = 0² + 2 (9.8) (1000)
v = 140 m/s
t = time taken to hit the ground
Using the equation
v = v₀ + at
140 = 0 + 9.8 t
t = 14.3 sec
Answer:
1.
Firstly removing off one strip and it leaves electrons behind, so the strip becomes positively charged.
2. The roll however is not negatively charged because it is "earthed " by the hand holding it, thus excess negatives repel each other away through the hand.
3.Tearing off the next strip and once more it leaves electrons behind, the new strip is also positively charged and will repel the first strip.
4. Then, tear two strips apart and one will leave electrons behind on the other. Meaning that one strip is positive and the other is negative and they will attract each other.
Answer:
the wave length becomes doubled or becomes two times the initial wavelength = 240 cm
Explanation:
From wave,
v = λf................ Equation 1
Where v = velocity of the wave, λ = wavelength of the wave, f = frequency of the wave.
Given: f = 1200 Hz, λ = 120 cm = 1.2 m
Substitute into equation 1
v = 1200(1.2)
v = 1440 m/s.
When the ship sent out a 600 Hz sound wave,
make λ the subject of formula in equation 1
λ = v/f............. Equation 2
Given: f = 600 Hz, v = 1440 m/s
Substitute into equation 2
λ = 1440/600
λ = 2.4 m or 240 cm.
When the ship sent out a 600 Hz sound wave instead, the wave length becomes doubled or becomes two times the initial wavelength = 240 cm
Solution for the problem is:
Total momentum before collision is always equal to total
momentum after collision. So note that:
Momentum of car A = 5000 x Xm/s
Momentum of car A + B = 15,000 x 2m/s
So combining the two, will give us the equation:
15,000/5,000 = 3
3 x 2 =6m/s
As per the question Bob drops the bag full with feathers from the top of the building.
The mass of the bag(m)= 1.0 lb
Let the air resistance is neglected.As the bag is under free fall ,hence the only force that acts on the bag is the force of gravity which is in vertical downward direction.
Here the acceleration produced on bag due to the free fall will be nothing else except the acceleration due to gravity i.e g =9.8 m/s^2
Here we are asked to calculate the distance travelled by the bag at the instant 1.5 s
Hence time t= 1.5 s
From equation of kinematics we know that -
S=ut + 0.5at^2 [ here S is the distance travelled]
For motion under free fall initial velocity (u)=0.
Hence S= 0×1.5+{0.5×(-9.8)×(1.5)^2}
⇒ -S =0-11.025 m
⇒ S= 11.025 m
=11 m
Here the negative sign is taken only due to the vertical downward motion of the body .we may take is positive depending on our frame of reference .
Hence the correct option is B.
