Explanation:
Galileo spacecraft was sent to orbit around and study Jupiter. It was launched on October 18, 1989 and entered into Jupiter's orbit on December 7, 1995. It had a lot of firsts in its name and most important of them was the first probe that entered in Jovian atmosphere. The spacecraft carried a probe named <em>Galileo</em> which separated from the spacecraft 5 months before it was to reach Jupiter. The separation was done in such a way that the rendezvous of probe and spacecraft with Jupiter coincided.
The mission was very challenging. Some of them are listed below:
1. Because of Jupiter's immense gravity the speed of the probe reached up to 47 KM/Sec as it approached Jupiter, but to enter into Jupiter's atmosphere it had to be brought down to subsonic level (0.34 KM/Sec). Due to this it had to withstand 228G deceleration.
2. Also, the time of probe entry had to be synchronized with that of the rendezvous of spacecraft with Jupiter. Very precise calculations were needed to achieve this.
3. Jupiter has a very thick atmosphere which would result in very high pressure and temperature for anything entering into it atmosphere. A very strong heat shield was needed to withstand such high pressure and temperature. Out of the 339 kg of the probe 152 kg was just the weight of the heat shield. Around 80 kg of the heat shield was lost during the entry. Its instruments were so sturdy that they worked till a pressure of 23 atm and temperature of 153°C.
4. The deceleration of the probe was further aided by using a parachute during the entry.
Answer: D
Explanation: D is the most reasonable answer because it's always good to plan ahead for anything, so if you were to plan ahead for future obstacles, then you can overcome them.
The average speed of Frank's car is 2 m/s and the average speed of Noah's car is 1.8 m/s.
<u>Explanation:</u>
Average speed is the measure of total distance covered at different time period. Since, the formula used for calculating the average speed is the ratio of total distance covered by each car to the time taken to cover that distance.
As there is only one set of data i.e., distance and time, the average speed will be equal to the speed of the car.
So in this case, the total distance covered by franks car is 300 cm = 3 m in 1.5 s. Then, the average speed will be
Similarly, the average speed of Noahs car which rolled a distance of 360 cm = 3.6 m in time 2 s, will be
Thus, the average speed of Frank's car is 2 m/s and the average speed of Noah's car is 1.8 m/s.
Answer:
B. t = 0.250s
Explanation:
A. An image with the sketch of the bat emitting a sound, which reflects on a surface and return to the bat is attached below.
B. In order to calculate the time that the pulse emitted by the bat, return to the bat, you first calculate the time that pulse takes to arrive to the object.
You use the following formula:
(1)
x: distance to the object = 43m
t: time = ?
v: speed of sound beat = 343 m/s
You solve the equation (1) for t:
The time on which the bat hears the echo is twice the value of t, that is:
The time on which bat heart the echo of its sound, from the moment on which bat emitted it, is 0.250s
Answer:
1.28 m
Explanation:
Given;
Radius, r = 1.5 cm = 0.015 m
Time, t = 19 s
Average angular speed = 4.5 rad/s
Consider a point when the tape is moving at a constant velocity along the circumference of the circular reel of radius r. The linear velocity v at this point is given by;
v = rω ----(1)
Where
v is the linear velocity of the circular motion
r is the radius of the reel
ω is the the angular velocity.
At a point the tap undergoes a linear motion before passing round the reel of the cassette. The linear velocity v at this point is given by;
v = L/t ----(2)
where;
v is the velocity of the linear motion
L is the length of the tape (distance covered by the tape)
t is the time taken
Equating equation(1) and equation (2)
L/t = rω
L = rωt
Substituting the given values,
L = 0.015 × 4.5 × 19
L = 1.2825 m
L = 1.28 m
