Answer: a) 456.66 s ; b) 564.3 m
Explanation: The time spend to cover any distance a constant velocity is given by:
v= distance/time so t=distance/v
The slower student time is: t=780m/0.9 m/s= 866.66 s
For the faster students t=780 m/1,9 m/s= 410.52 s
Therefore the time difference is 866.66-410.52= 456.14 s
In order to calculate the distance that faster student should walk
to arrive 5,5 m before that slower student, we consider the follow expressions:
distance =vslower*time1
distance= vfaster*time 2
The time difference is 5.5 m that is equal to 330 s
replacing in the above expression we have
time 1= 627 s
time2 = 297 s
The distance traveled is 564,3 m
Answer:
.
Assumptions:
- The object is dropped in a free fall.
- There's no air resistance.
- The downward acceleration due to gravity is
Explanation:
Consider the "SUVAT" equation
,
where
- is the final velocity,
- is the initial velocity,
- is the acceleration of the object, and
- is the change in the object's position.
For example, if the bottle needs to achieve a speed of by the time it reaches the ground,
- since the statement that the bottle is "dropped" implies a free fall.
- .
Apply the previous equation to find the minimum height, :
.
Replace the value and apply the formula to find the minimum height required to reach different final speeds.
By wave particle duality.
Wavelength , λ = h / mv
where h = Planck's constant = 6.63 * 10⁻³⁴ Js, m = mass in kg, v = velocity in m/s.
m = 1kg, v = 4.5 m/s
λ = h / mv
λ = (6.63 * 10⁻³⁴) /(1*4.5)
λ ≈ 1.473 * 10⁻³⁴ m
Option D.
Answer:
The two helicopters have the same kinetic energy, but a different GPE, or gravitational potential energy.
Explanation:
Answer:
a = 0.63 m/s²
Explanation:
given,
mass of submarine = 1460-kg
upward buoyant force = 16670 N
downward resistive force = 1150 N
submarine acceleration = ?
assuming g = 10 m/s²
now,
B - (R + mg) = ma
16670 - 1150 - 1460 × 10 = 1460 × a
1460× a = 920
a = 0.63 m/s²
hence, the acceleration of submarine is equal to a = 0.63 m/s²