Question:
A skateboarder jumps horizontally off the top of a staircase at a speed of 14.5 and lands at bottom of the stairs. The staircase has a horizontal length of 8.00 m. We can ignore air resistance. What is the skater's vertical displacement during the jump?
Answer:
y = 1.48 m
Explanation:
Projectile motion is a two dimensional motion experienced by an object or particle that is subjected near the Earth's surface and moves along a curved path under the influence of gravity only. The path followed by projectile motion is called projectile path.
As the skateboarder followed the projectile path, and we know that in projectile motion the horizontal component of the velocity remain constant throughout his motion. So there is no acceleration along horizontal path.
Also Skateboard jumps horizontally, So initial velocity has only horizontal component.
Horizontal component of initial velocity = 
= 14.5 m/s
Horizontal displacement = x = 8.00 m
Vertical displacement = y = ?
Using the following formula
x = t
8 = (14.5)(t)
t = 0.55 s
As skateboarder jumps horizontally, So there is no vertical component of velocity.
According to 2nd equation of motion
y = 
As 
So
y = 0.5gt²
y = 0.5*9.8*(0.55)²
y = 1.48 m
Answer:
the pull or push which changes or tends to change the position of an object from rest to motion or motion to rest is called force.
Changes of force that can be produced:
- Force can change the shape of a body.
- Force can change the position of a body.
- Force can stop the moving body.
- Force can change the speed of a moving body.
- Force can change the direction of a moving body.
Answer:
Explanation:
Given that,
Force is downward I.e negative y-axis
F = -2 × 10^-14 •j N
Magnetic field is westward, +x direction
B = 8.3 × 10^-2 •i T
Charge of an electron
q = 1.6 × 10^-19C
Velocity and it direction?
Force in a magnetic field is given as
F = q(V×B)
Angle between V and B is 270, check attachment
The cross product of velocity and magnetic field
F =qVB•Sin270
2 × 10^-14 = 1.6 × 10^-19 × V × 8.3 × 10^-2
Then,
v = 2 × 10^-14 / (1.6 × 10^-19 × 8.3 × 10^-2)
v = 1.51 × 10^6 m/s
Direction of the force
Let x be the direction of v
-F•j = v•x × B•i
From cross product
We know that
i×j = k, j×i = -k
j×k =i, k×j = -i
k×i = j, i×k = -j OR -k×i = -j
Comparing -k×i = -j to given problem
We notice that
-F•j = q ( -V•k × B×i)
So, the direction of V is negative z- direction
V = -1.51 × 10^6 •k m/s
Answer:
1. 5 V
2. A₂ = 1.2 A
Explanation:
1. Determination of the voltage measured at R₃.
Voltage at R₁ (V₁) = 1 V
Voltage at R₂ (V₂) = 6 V
Total voltage (Vₜ) = 12 V
Voltage at R₃ (V₃) =.?
Vₜ = V₁ + V₂ + V₃
12 = 1 + 6 + V₃
12 = 7 + V₃
Collect like terms
12 – 7 = V₃
V₃ = 5 V
Thus, the voltage measured at R₃ is 5 V
2. Determination of A₂.
From the circuit diagram, we can see that the resistors are in series arrangement. This means that the same current will pass through each resistor.
Thus,
A₂ = A₁ = 1.2 A
The equation for work is W=DxF
W being work
D being distance
F being force
That would make the equation
8x.5=4
