Answer:
3.467 s
Explanation:
given,
distance , d = 49 mm = 0.049 m
initial speed of the of the rock, v = 17 m/s
time taken by the Heather rock to reach water
using equation of motion

taking downward as negative

4.9 t² + 17 t - 0.049 = 0
now,
t₁ = -3.47 s , 0.0028 s
rejecting negative values
t₁ = 0.0028 s
now, time taken by the ball of Jerry
using equation of motion

taking downward as negative

4.9 t² - 17 t - 0.049 = 0
now,

t₂ = 3.47 s ,-0.0028 s
rejecting negative values
t₂ = 3.47 s
now, time elapsed is = t₂ - t₁ = 3.47 - 0.0028 = 3.467 s
Answer:

Explanation:
As we know that the electrostatic force is a based upon inverse square law
so we have

now since it depends inverse on the square of the distance so we can say

now we know that


also we know that

now from above equation we have



Answer:
W = 112.58 N-unit
Explanation:
Given:
- Force F = 10 N
- Angle Q of force with x axis: 30 degrees
- distance to be moved d = 13 units along + x axis
Find:
Work Done by the force F:
Solution:
The work by force in positive x direction can only be done if the both the direction of distance traveled and direction of force are parallel vectors. Hence we compute the component of Force F in x direction F_x:
F_x = F*cos(Q)
F_x = 10*cos(30)
F_x = 8.66 N
Hence,
Work Done by force
W = F_x * d
W = 8.66 * 13
W = 112.58 N-unit
"per second" is exactly the definition of "Hertz".
50 per second is 50 Hz. (B)
Answer:
2.83×10⁻¹¹ N.
Explanation:
From the question,
Using
F = qvB....................... Equation 1
Where F = magnetic force acting on the duck, q = charge of the duck, v = velocity of the duck, B = magnetic field of the duck.
Given: q = 6.47×10⁻⁸ C, B = 4.09×10⁻⁵ T, v = 10.7 m/s.
Substitute these values into equation 1
F = 6.47×10⁻⁸×4.09×10⁻⁵×10.7
F = 2.83×10⁻¹¹ N.
Hence the magnetic force acting on the duck is 2.83×10⁻¹¹ N.