4,947 research outputs found

    Designing Effective Questions for Classroom Response System Teaching

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    Classroom response systems (CRSs) can be potent tools for teaching physics. Their efficacy, however, depends strongly on the quality of the questions used. Creating effective questions is difficult, and differs from creating exam and homework problems. Every CRS question should have an explicit pedagogic purpose consisting of a content goal, a process goal, and a metacognitive goal. Questions can be engineered to fulfil their purpose through four complementary mechanisms: directing students' attention, stimulating specific cognitive processes, communicating information to instructor and students via CRS-tabulated answer counts, and facilitating the articulation and confrontation of ideas. We identify several tactics that help in the design of potent questions, and present four "makeovers" showing how these tactics can be used to convert traditional physics questions into more powerful CRS questions.Comment: 11 pages, including 6 figures and 2 tables. Submitted (and mostly approved) to the American Journal of Physics. Based on invited talk BL05 at the 2005 Winter Meeting of the American Association of Physics Teachers (Albuquerque, NM

    Spitzer Phase Curves of KELT-1b and the Signatures of Nightside Clouds in Thermal Phase Observations

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    We observed two full orbital phase curves of the transiting brown dwarf KELT-1b, at 3.6um and 4.5um, using the Spitzer Space Telescope. Combined with previous eclipse data from Beatty et al. (2014), we strongly detect KELT-1b's phase variation as a single sinusoid in both bands, with amplitudes of 964±36964\pm36 ppm at 3.6um and 979±54979\pm54 ppm at 4.5um, and confirm the secondary eclipse depths measured by Beatty et al. (2014). We also measure noticeable Eastward hotspot offsets of 28.4±3.528.4\pm3.5 degrees at 3.6um and 18.6±5.218.6\pm5.2 degrees at 4.5um. Both the day-night temperature contrasts and the hotspot offsets we measure are in line with the trends seen in hot Jupiters (e.g., Crossfield 2015), though we disagree with the recent suggestion of an offset trend by Zhang et al. (2018). Using an ensemble analysis of Spitzer phase curves, we argue that nightside clouds are playing a noticeable role in modulating the thermal emission from these objects, based on: 1) the lack of a clear trend in phase offsets with equilibrium temperature, 2) the sharp day-night transitions required to have non-negative intensity maps, which also resolves the inversion issues raised by Keating & Cowan (2017), 3) the fact that all the nightsides of these objects appear to be at roughly the same temperature of 1000K, while the dayside temperatures increase linearly with equilibrium temperature, and 4) the trajectories of these objects on a Spitzer color-magnitude diagram, which suggest colors only explainable via nightside clouds.Comment: AJ in press. Updated to reflect the accepted versio

    The impact of the direct payment of housing benefit: evidence from Great Britain

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    In recent years, a number of welfare reforms have been introduced in the UK by Conservative-led governments. The most high profile of these is Universal Credit (UC), which is currently being rolled out across the country. A key feature of UC is a change in the way the income-related housing allowance for social housing tenants (Housing Benefit) is administered, as under UC, it is paid directly to tenants (direct payment), who are responsible for paying their rent. This represents a step change for them as for more than 30 years landlord payment has been the norm in the UK. There has been little research into direct payment. This paper seeks to address this gap in knowledge by presenting the key findings of an initiative designed to trial direct payment. It finds that many tenants experienced difficulties on direct payment. Reflecting this, landlords' arrears rose markedly

    Planning the Future of U.S. Particle Physics (Snowmass 2013): Chapter 4: Cosmic Frontier

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    These reports present the results of the 2013 Community Summer Study of the APS Division of Particles and Fields ("Snowmass 2013") on the future program of particle physics in the U.S. Chapter 4, on the Cosmic Frontier, discusses the program of research relevant to cosmology and the early universe. This area includes the study of dark matter and the search for its particle nature, the study of dark energy and inflation, and cosmic probes of fundamental symmetries.Comment: 61 page

    The impact on welfare and public finances of job loss in industrial Britain

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    It is important to take a long view of many economic problems. This paper explains how the large-scale loss of industrial jobs in parts of Britain during the 1980s and 1990s still inflates the contemporary budget deficit in the UK. Drawing on the findings of several empirical studies by the authors, it shows that although there has been progress in regeneration the consequences of job loss in Britain’s older industrial areas have been near-permanently higher levels of worklessness, especially on incapacity benefits, low pay, and a major claim on present-day public finances to pay for both in-work and out-of-work benefits. Furthermore, as the UK government implements reductions in welfare spending the poorest places are being hit hardest. In effect, communities in older industrial Britain now face punishment in the form of welfare cuts for the destruction previously wrought to their industrial base

    The impact on welfare and public finances of job loss in industrial Britain

    Get PDF
    It is important to take a long view of many economic problems. This paper explains how the large-scale loss of industrial jobs in parts of Britain during the 1980s and 1990s still inflates the contemporary budget deficit in the UK. Drawing on the findings of several empirical studies by the authors, it shows that although there has been progress in regeneration the consequences of job loss in Britain’s older industrial areas have been near-permanently higher levels of worklessness, especially on incapacity benefits, low pay, and a major claim on present-day public finances to pay for both in-work and out-of-work benefits. Furthermore, as the UK government implements reductions in welfare spending the poorest places are being hit hardest. In effect, communities in older industrial Britain now face punishment in the form of welfare cuts for the destruction previously wrought to their industrial base

    The pupil's response to affective pictures: Role of image duration, habituation, and viewing mode

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    The pupil has been shown to be sensitive to the emotional content of stimuli. We examined this phenomenon by comparing fearful and neutral images carefully matched in the domains of luminance, image contrast, image color, and complexity of content. The pupil was more dilated after viewing affective pictures, and this effect was (a) shown to be independent of the presentation time of the images (from 100–3,000 ms), (b) not diminished by repeated presentations of the images, and (c) not affected by actively naming the emotion of the stimuli in comparison to passive viewing. Our results show that the emotional modulation of the pupil is present over a range of variables that typically vary from study to study (image duration, number of trials, free viewing vs. task), and encourages the use of pupillometry as a measure of emotional processing in populations where alternative techniques may not be appropriate

    Status of ANITA and ANITA-lite

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    We describe a new experiment to search for neutrinos with energies above 3 x 10^18 eV based on the observation of short duration radio pulses that are emitted from neutrino-initiated cascades. The primary objective of the ANtarctic Impulse Transient Antenna (ANITA) mission is to measure the flux of Greisen-Zatsepin-Kuzmin (GZK) neutrinos and search for neutrinos from Active Galactic Nuclei (AGN). We present first results obtained from the successful launch of a 2-antenna prototype instrument (called ANITA-lite) that circled Antarctica for 18 days during the 03/04 Antarctic campaign and show preliminary results from attenuation length studies of electromagnetic waves at radio frequencies in Antarctic ice. The ANITA detector is funded by NASA, and the first flight is scheduled for December 2006.Comment: 9 pages, 8 figures, to be published in Proceedings of International School of Cosmic Ray Astrophysics, 14th Course: "Neutrinos and Explosive Events in the Universe", Erice, Italy, 2-13 July 200

    Ultra-Relativistic Magnetic Monopole Search with the ANITA-II Balloon-borne Radio Interferometer

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    We have conducted a search for extended energy deposition trails left by ultra-relativistic magnetic monopoles interacting in Antarctic ice. The non-observation of any satisfactory candidates in the 31 days of accumulated ANITA-II flight data results in an upper limit on the diffuse flux of relativistic monopoles. We obtain a 90% C.L. limit of order 10^{-19}/(cm^2-s-sr) for values of Lorentz boost factor 10^{10}<gamma at the anticipated energy E=10^{16} GeV. This bound is stronger than all previously published experimental limits for this kinematic range.Comment: updated to version accepted by Phys. Rev.
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