Question:
A 5000 kg rocket is set for vertical firing. The exhaust speed is 800 m/s. To give an initial upward acceleration of 20$m/s^{2},$ the amount of gas ejected per second to supply the needed thrust will be (Take g = 10 $m/s^{2}$)
A 5000 kg rocket is set for vertical firing. The exhaust speed is 800 m/s. To give an initial upward acceleration of 20$m/s^{2},$ the amount of gas ejected per second to supply the needed thrust will be (Take g = 10 $m/s^{2}$)
Updated On: Apr 28, 2025
- 127.5 kg/s
- 137.5 kg/s
- 155.5 kg/s
- 187.5 kg/s
Hide Solution
Verified By Collegedunia
The Correct Option is D
Solution and Explanation
Given : Mass of rocket (m) = 5000 Kg
Exhaust speed (v) = 800 m/s
Acceleration of rocket (a) = 20 $m/s^{2}$
Gravitational acceleration (g) $=10 m/s^{2}$
We know that upward force
F = m(g +a) = 5000(10+20)
= 5000 x 30 = 150000 N.
We also know that amount of gas ejected
$\left(\frac{d m}{d t}\right)=\frac{F}{V}=\frac{150000}{800}=187.5 $ kg/s
Exhaust speed (v) = 800 m/s
Acceleration of rocket (a) = 20 $m/s^{2}$
Gravitational acceleration (g) $=10 m/s^{2}$
We know that upward force
F = m(g +a) = 5000(10+20)
= 5000 x 30 = 150000 N.
We also know that amount of gas ejected
$\left(\frac{d m}{d t}\right)=\frac{F}{V}=\frac{150000}{800}=187.5 $ kg/s
Was this answer helpful?
2
0
Top Questions on Rotational motion
- A solid sphere of radius 18 cm is rolling down from rest from the top of an inclined plane of length 14 m and angle of inclination $30^\circ$. The time taken by the sphere to reach the bottom of the inclined plane is (Acceleration due to gravity = $10~\text{m s}^{-2}$)
- TS EAMCET - 2025
- Physics
- Rotational motion
- A uniform circular disc of mass $\dfrac{\pi}{40}$ kg is rotating about an axis passing through its center and perpendicular to its plane with an angular speed of 150 rev/min. If the angular momentum of the disc is 6.25 Js, then its radius is:
- TS EAMCET - 2025
- Physics
- Rotational motion
- Three thin uniform rods each of mass \( M \) and length \( L \) are placed along the three axes of a Cartesian coordinate system with one end of all the rods at origin. The moment of inertia of the system of the rods about z-axis is
- AP EAPCET - 2025
- Physics
- Rotational motion
- A disc of moment of inertia \( I \) is rotating with angular velocity \( \omega \). A ring of the same mass and radius, initially at rest, is gently placed coaxially on top of the disc. What is the final angular velocity of the system?
- BITSAT - 2025
- Physics
- Rotational motion
- A solid sphere of mass 2 kg and radius 0.5 m rolls without slipping down an inclined plane of height 3 m. What is its speed at the bottom? (Take \( g = 9.8\, \text{m/s}^2 \))
- BITSAT - 2025
- Physics
- Rotational motion
View More Questions
Questions Asked in NEET exam
- An oxygen cylinder of volume 30 litre has 18.20 moles of oxygen. After some oxygen is withdrawn from the cylinder, its gauge pressure drops to 11 atmospheric pressure at temperature \(27^\circ\)C. The mass of the oxygen withdrawn from the cylinder is nearly equal to: [Given, \(R = \frac{100}{12} \text{ J mol}^{-1} \text{K}^{-1}\), and molecular mass of \(O_2 = 32 \text{ g/mol}\), 1 atm pressure = \(1.01 \times 10^5 \text{ N/m}^2\)]
- NEET (UG) - 2025
- Ideal-gas equation and absolute temperature
- The plates of a parallel plate capacitor are separated by d. Two slabs of different dielectric constant \(K_1\) and \(K_2\) with thickness \(d/2\) and \(d/2\) respectively are inserted in the capacitor. Due to this, the capacitance becomes two times larger than when there is nothing between the plates. If \(K_1 = 1.25 K_2\), the value of \(K_2\) is :
- NEET (UG) - 2025
- Capacitors and Capacitance
A full wave rectifier circuit with diodes (\(D_1\)) and (\(D_2\)) is shown in the figure. If input supply voltage \(V_{in} = 220 \sin(100 \pi t)\) volt, then at \(t = 15\) msec:
- NEET (UG) - 2025
- Semiconductor Diode
- A microscope has an objective of focal length \(f_o = 2\) cm and an eyepiece of focal length \(f_e = 4\) cm. The tube length of the microscope is \(L = 40\) cm. If the distance of distinct vision of eye is \(D = 25\) cm, the magnification in the microscope is:
- NEET (UG) - 2025
- Optical Instruments
- Given below are two statements:
Statement I: In an ecosystem, there is unidirectional flow of energy of sun from producers to consumers.
Statement II: Ecosystems are exempted from the law of thermodynamics.
View More Questions
Concepts Used:
Rotational Motion
Rotational motion can be defined as the motion of an object around a circular path, in a fixed orbit.
Rotational Motion Examples:
The wheel or rotor of a motor, which appears in rotation motion problems, is a common example of the rotational motion of a rigid body.
Other examples:
- Moving by Bus
- Sailing of Boat
- Dog walking
- A person shaking the plant.
- A stone falls straight at the surface of the earth.
- Movement of a coin over a carrom board
Types of Motion involving Rotation:
- Rotation about a fixed axis (Pure rotation)
- Rotation about an axis of rotation (Combined translational and rotational motion)
- Rotation about an axis in the rotation (rotating axis)