Science questions with answers, page 3

275 solved Science MCQs from SSC, RRB, banking and police exams. Open any question to try it and read the explanation. Want a timed test instead? Free Science practice sets.

According to Newton's Third Law of Motion, every action force has an equal and opposite:
Match List-I (Disease) with List-II (Type of causative organism): List-I: (a) Ringworm (b) Rabies (c) Sleeping sickness (d) Diphtheria List-II: (i)…
Match List-I (heavy metal) with List-II (health effect associated with its poisoning): List-I: (a) Mercury (b) Cadmium (c) Arsenic (d) Lead List-II…
Two resistances of 40 Ω each are connected in parallel. This combination is then connected in series with a third resistance of 30 Ω and a 10 V…
Two ideal gases A and B have molecular weights in the ratio 1:3. Equal masses of A and B are mixed to form a gas mixture with total pressure P atm…
Which of the following is in accordance with the Law of Constant Proportions? a. In ammonia (NH3), the ratio of the mass of nitrogen to the mass of…
The transfer of heat through a medium without actual movement of the particles of the medium is called:
The human eye's ability to focus on objects at varying distances is called
Ribosomes are the site of:
Transpiration in plants mainly occurs through:
The pollen needs to be transferred from the stamen to the stigma. If this transfer of pollen occurs in the same flower, this phenomenon is known as:
The gland known as the master gland of the body is the:
Which of the following metals is a liquid at room temperature?
Diamond and graphite are both made entirely of carbon atoms; such different forms of the same element are called:
A wooden block of mass 50 kg is placed on a smooth horizontal surface. A constant horizontal force of 'X' N is applied on it while it is at rest…
Which of the following gases are found in coal mines and marshy places ?
If two isotopes of an element ‘X’ are X-35 and X-37, the average atomic mass of chlorine (if X-35 = 25% and X-37 = 75%) will be:
A car travels 120 km at an average speed of 60 km/h and immediately returns along the same route covering the distance in 1.5 hour(s). What is the…
A cyclist travels 90 km at an average speed of 30 km/h and immediately returns along the same route, covering the return distance in 2 hours. What…
Two resistances of 20 Ω each are connected in parallel. This combination is then connected in series with a third resistance of 20 Ω and a 3 V…
Which combination best represents essential life processes for maintaining an individual organism?
The sulphide ores of metals, which lie in the middle of activity series, are first converted to oxides. The necessary condition for this conversion…
Which fine, thread-like structures on plant roots greatly increase the surface area available for absorbing water and minerals from the soil?
Which of the following minerals has kieserite as its ore ?
Which pair of organs produces the female gamete (ovum) and secretes the hormones estrogen and progesterone?
The Svalbard Global Seed Vault, a 'doomsday' store of crop seeds for ex-situ conservation, is located in:
Which of these nutrients is primarily needed for the growth and repair of body tissues?
Ammonia gas, which has a pungent smell and is widely used to manufacture nitrogen fertilisers, has which chemical formula?
Which vitamin is essential for the normal clotting of blood?
The transfer of heat through a fluid due to actual movement of the fluid particles is called:
A body covers a straight-line distance of 15 m from point A to B in 3 s and then covers back the distance from point B to point A along the same…
The echo of the sound of a boy standing in front of a mountain is heard after 0.2 s. What is the distance of the mountain from the boy when speed of…
A girl walks from one end A to the other end B of a straight 800 m road in 2 minutes and then turns around and walks 200 m back to point C in…
Amit had invested same amount of sums at simple as well as compound interest, compounded annually. The time period of both the sums was 2 years and…
A car travels 90 km at an average speed of 45 km/h and immediately returns along the same route covering the distance in 1.2 hour(s). What is the…
A body covers a straight-line distance of 18 m from point A to B in 6 s, and then returns from B to A along the same path in 9 s. What is the…
Two resistances of 30 Ω each are connected in parallel. This combination is then connected in series with a third resistance of 25 Ω and a 6 V…
Two wires A and B are made of the same material and have the same length but different cross-sectional areas. If the resistance of wire A is 9 times…
Which of the following materials is commonly used as a semiconductor in electronic devices?
The process of extracting a pure metal from its molten ore using electricity is called:
Which of the following is the formula of barium peroxide.
An electric heater of 1500 watt is used for 4 hours every day. How many units (kWh) of electricity will it consume in the month of June?
A cross between organisms differing in two traits is called a:
Malaria in humans is most commonly transmitted through the bite of the female mosquito of which genus?
Producers in a field fix 20,000 units of energy. Following the 10% law, how much energy is available to the tertiary consumers (the fourth trophic…
An electric refrigerator has a power rating of 500 W and is used for 6 hours each day. If the cost of electrical energy is ₹4.00 per kilowatt-hour…
An electric geyser rated 1500 W is used for 2 hours every day. How many units of electricity does it consume in 30 days?
An electric heater of 2000 watt is used for 3 hours every day. The number of units (kWh) of electricity consumed in 30 days is
An electric water heater rated 800 watts is used for 5 hours every day for 30 days. The number of units (kilowatt-hours) of electricity consumed is
An electric heater of 1,500 W is used for 4 hours every day. How many units of electricity will it consume in 30 days?
An electric heater rated 2 kW is used for 3 hours a day for 30 days. How many units (kWh) of electricity does it consume?
An electric heater of 2 kW is used for 3 hours a day for 30 days. If the tariff is ₹5 per unit, the electricity bill for the heater is
An electric heater rated 2,000 watts is used for 3 hours a day for 30 days. The number of units (kWh) of electricity consumed is
A uniform wire of resistance 5 ohm is stretched uniformly so that its length becomes double. Its new resistance will be
A force of 20 N moves an object through a distance of 5 m in the direction of the force. Find the work done.
An electric heater rated 2 kW is used for 3 hours daily. How many units (kWh) of electricity does it consume in the month of April?
0.25 g of an organic compound gave 0.13 g of water after complete combustion. The percentage composition of hydrogen is _________.
A solution contains 25 g of copper chloride salt in 250 g of water. Calculate the concentration in terms of mass by mass percentage of the solution.
Convert 50°C to the Fahrenheit scale using °F = (9/5 × °C) + 32.
The simple interest on a principal amount (in ₹) is ₹284 for a period of 2 years at the rate of 5% per annum. The principal amount (in ₹) is:
The amount of work done in moving a charge of 4C across two points having a potential difference of 6V is ______ .
A sound wave has a speed of 320 m/s. If the wavelength of the wave is 0.4 m, what is the frequency of this wave?
A force of 20 N moves a box through 5 m in the direction of the force. How much work is done?
An electric heater of 2 kW is used for 3 hours. How many units (kWh) of electrical energy does it consume?
If the power of a lens is +1 Dioptre, then the focal length of the lens will be:
What will be the focal length of a convex lens with the power of a +2.5 Diopter?
Two resistance of 2Ω and 6Ω are connected in series and this combination is connected across a 12 V bettery. Find the power supplied by the battery.
Two resistors of 10Ω and 20 Ω area connected in series and this combination is connected across a 30 V supply voltage. Find the voltage across the…
The adult human skeleton of 206 bones has 80 bones in the axial skeleton. How many bones form the appendicular skeleton?
A car runs for one hour with a speed 60 km per hour, for 2 hours with a speed 70 km per hour and for 5 hours with a speed 50 km per hour. What is…
The present age ratio of the mother to the daughter is 7: 2. After 12 years, their ages will be in the ratio of 9: 4. What is the current age of the…
Consider several electric bulbs designed to be used on a 240 V electric supply line. The bulbs are rated as 10 W. How many bulbs can be connected in…
A force of 10 N moves an object through a distance of 5 m in the direction of the force. Find the work done.
If a force of 6 N is applied on a body, which is displaced 2m in the direction of force, then find the work done.
A sound wave has a frequency of 1600 Hz. If the wavelength of the wave is 0.2 m, what will be the speed of the wave?