591: Microbial fuel cells are considered a source of sustainable energy, Why ?
1. They use living organisms as catalysts to generate electricity from certain substrates.
2. They use a variety of inorganic materials as substrates.
3. They can be installed in waste water treatment plants to cleanse water and produce electricity.
Which of the Statements given above is/are correct?
(a) 1 only
(b) 1 and 3 only
(c) 2 and 3 only
(d) 1, 2 and 3
Explanation:
A microbial fuel cell (MFC) or biological fuel cell is a bio-electrochemical system that drives a current by mimicking bacterial interactions found in nature. A microbial fuel cell is a device that converts chemical energy to electrical energy by the catalytic reaction of microorganisms. Microbial fuel cells have a number of potential used. The most readily apparent is harvesting electricity produced for use as a power source. Virtually any organic material could be used to feed the fuel cell, including coupling cells to wastewater treatment plants.
The substrates used in microbial fuel cells are of organic origin which include glucose, acetate, arabitol, carboxymethyl cellulose, corn stover biomass, ethanol, farm manure, Furfural, Galactitol, Glucuronic acid Lactate, Landfill leachate, Phenol, Propionate, Sodium formate, etc.
592: Consider the following statements :
The price of any currency in international market is decided by the
I. World Bank.
II. demand for goods/services provided by the country concerned.
III. stability of the government of the concerned country.
IV. economic potential of the country in question.
Of these statements :
(a) I, II, III and IV are correct
(b) II and III are correct
(c) III and IV are correct
(d) I and IV are correct
Explanation:
The price of any currency in International market is determined by the demand for goods/services provided by the country and the stability of the government of the concerned country.
593: Which of the following statements is/are correct regarding the Maternity Benefit (Amendment) Act, 2017?
1. Pregnant women are entitled for three months pre-delivery and three months post-delivery paid leave.
2. Enterprises with creches must allow the mother minimum six creche visits daily.
3. Women with two children get reduced entitlements.
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 2 only
(c) 3 only
(d) 1, 2 and 3
Explanation:
This new bill amends the Maternity Benefit Act of 1961. Under the new provision, women are entitled to visit creches four times a day. Maternity benefit of 26 weeks are provided. Out of 26 weeks, Up to eight weeks can be claimed before delivery. However, one can instead take the entire 26 weeks of leave after the delivery. If the woman has more than two surviving children, the maternity benefit is for 12 weeks only.
Source: https://www.livemint.com/money/personal-finance/the-benefits-women-are-entitled-to-and-the-rights-they-can-claim-under-maternity-1557655754106.html
594: There are mice in the field which act as prey to snakes. Hawks eat the snakes. Some dogs are brought into the field ? What will be its effect?
(a) Mice will decrease
(b) Hawks will decrease
(c) Snakes will increase
(d) Mice and snakes will decrease
595: A weightless rubber balloon is filled with 200 cc of water. Its weight in water is equal to:
(a) (9.8/5) N
(b) (9.8/10) N
(c) (9.8/2) N
(d) zero
Explanation:
Upthrust acting on the ballon is equal to the fluid displaced. Here upthrust is equal to the weight of water in ballon. Therefore, net weight in water will be zero.