The resultant velocity is 360.81 m/s and the velocity of the dolphin swims is 11 m/s
Explanation:
The boat travelling is 13.4 m/s
The captain walks on the deck is 1.3 m/s
The resultant velocity = a² + b² = c²
= 13.4² + 1.3²
= 179.56 + 1.69
c² =
c= 360.81 m/s
To find the velocity, the dolphin swims in 55 m and the acceleration is 5.0 s
velocity = distance / acceleration
=
= 11 m/s
Therefore, the velocity is 11 m/s.
Answer:
Ratio of power produced by new to old car is 16:1
Explanation:
Assuming both cars have the same mass m
Let KE1 and KE2 be the kinetic energies of the old and new car respectively.
v1 = v
and v2 = 4v
KE1 = 1/2mv1² = 1/2mv²
KE2 = 1/2mv2² = 1/2m(4v)² = 1/2×m×16v² = 8mv²
Ratio of the power produced by the new car to the old one is simply KE2/KE1 =8mv²/1/2mv² = 16
Since the same time interval is given.
Answer:
D (50m)
Explanation:
If distance is speed × time
That would be 5m/s × 10s
So the final answer will be 50m.
Blessings
Answer:
1.4 * 10 ^-1 Ω
Explanation:
Hi,
For this question, we gotta use the formula
R = pL/A
p = The resistivity of your material at 20°C
L = length of the wire
A = cross-sectional area
The resistivity of tungsten is 5.60 * 10^-8 at 20°C
By plugging the values, we get:
R = (5.60 * 10^-8)(2.0)/(7.9*10^-7) = 1.4 * 10 ^-1 Ω
(a) 907.5 N/m
The force applied to the spring is equal to the weight of the object suspended on it, so:
The spring obeys Hook's law:
where k is the spring constant and is the stretching of the spring. Since we know , we can re-arrange the equation to find the spring constant:
(b) 1.45 cm
In this second case, the force applied to the spring will be different, since the weight of the new object is different:
So, by applying Hook's law again, we can find the new stretching of the spring (using the value of the spring constant that we found in the previous part):
(c) 3.5 J
The amount of work that must be done to stretch the string by a distance is equal to the elastic potential energy stored by the spring, given by:
Substituting k=907.5 N/m and , we find the amount of work that must be done: